The game crashed whilst initializing game
Error: java.lang.RuntimeException: Could not execute entrypoint stage 'main' due to errors, provided by 'medievalweapons'!
Exit Code: -1

09:58:21.436
WorldEdit for Fabric (version 7.2.6+4b2d1e7) is loaded
09:58:22.445

---- Minecraft Crash Report ----
// Uh... Did I do that?

Time: 10/3/21, 9:58 AM
Description: Initializing game

java.lang.RuntimeException: Could not execute entrypoint stage 'main' due to errors, provided by 'medievalweapons'!
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointUtils.invoke0(EntrypointUtils.java:50)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointUtils.invoke(EntrypointUtils.java:33)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointClient.start(EntrypointClient.java:33)
at net.minecraft.class_310.(class_310.java:457)
at net.minecraft.client.main.Main.main(Main.java:179)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:567)
at net.fabricmc.loader.game.MinecraftGameProvider.launch(MinecraftGameProvider.java:234)
at net.fabricmc.loader.launch.knot.Knot.launch(Knot.java:153)
at net.fabricmc.loader.launch.knot.KnotClient.main(KnotClient.java:28)
Caused by: java.lang.NoClassDefFoundError: net/fabricmc/fabric/api/tag/TagFactory
at net.medievalweapons.init.TagInit.(TagInit.java:10)
at net.medievalweapons.MedievalMain.onInitialize(MedievalMain.java:29)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointUtils.invoke0(EntrypointUtils.java:47)
... 11 more
Caused by: java.lang.ClassNotFoundException: net.fabricmc.fabric.api.tag.TagFactory
at java.base/jdk.internal.loader.BuiltinClassLoader.loadClass(BuiltinClassLoader.java:636)
at java.base/jdk.internal.loader.ClassLoaders$AppClassLoader.loadClass(ClassLoaders.java:182)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:519)
at net.fabricmc.loader.launch.knot.KnotClassLoader.loadClass(KnotClassLoader.java:175)
at java.base/java.lang.ClassLoader.loadClass(ClassLoader.java:519)
... 14 more

A detailed walkthrough of the error, its code path and all known details is as follows:

-- Head --
Thread: Render thread
Stacktrace:
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointUtils.invoke0(EntrypointUtils.java:50)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointUtils.invoke(EntrypointUtils.java:33)
at net.fabricmc.loader.entrypoint.minecraft.hooks.EntrypointClient.start(EntrypointClient.java:33)
at net.minecraft.class_310.(class_310.java:457)

-- Initialization --
Details:
Stacktrace:
at net.minecraft.client.main.Main.main(Main.java:179)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:78)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:567)
at net.fabricmc.loader.game.MinecraftGameProvider.launch(MinecraftGameProvider.java:234)
at net.fabricmc.loader.launch.knot.Knot.launch(Knot.java:153)
at net.fabricmc.loader.launch.knot.KnotClient.main(KnotClient.java:28)

-- System Details --
Details:
Minecraft Version: 1.17.1
Minecraft Version ID: 1.17.1
Operating System: Windows 10 (amd64) version 10.0
Java Version: 16.0.1, Microsoft
Java VM Version: OpenJDK 64-Bit Server VM (mixed mode), Microsoft
Memory: 1209734968 bytes (1153 MiB) / 1711276032 bytes (1632 MiB) up to 2147483648 bytes (2048 MiB)
CPUs: 8
Processor Vendor: GenuineIntel
Processor Name: Intel(R) Core(TM) i7-7700HQ CPU @ 2.80GHz
Identifier: Intel64 Family 6 Model 158 Stepping 9
Microarchitecture: Kaby Lake
Frequency (GHz): 2.81
Number of physical packages: 1
Number of physical CPUs: 4
Number of logical CPUs: 8
Graphics card #0 name: Intel(R) HD Graphics 630
Graphics card #0 vendor: Intel Corporation (0x8086)
Graphics card #0 VRAM (MB): 1024.00
Graphics card #0 deviceId: 0x591b
Graphics card #0 versionInfo: DriverVersion=27.20.100.8587
Graphics card #1 name: NVIDIA GeForce GTX 1060
Graphics card #1 vendor: NVIDIA (0x10de)
Graphics card #1 VRAM (MB): 4095.00
Graphics card #1 deviceId: 0x1c20
Graphics card #1 versionInfo: DriverVersion=27.21.14.5206
Memory slot #0 capacity (MB): 8192.00
Memory slot #0 clockSpeed (GHz): 2.40
Memory slot #0 type: DDR4
Memory slot #1 capacity (MB): 8192.00
Memory slot #1 clockSpeed (GHz): 2.40
Memory slot #1 type: DDR4
Virtual memory max (MB): 27522.95
Virtual memory used (MB): 13327.04
Swap memory total (MB): 11247.83
Swap memory used (MB): 199.35
JVM Flags: 9 total; -XX:HeapDumpPath=MojangTricksIntelDriversForPerformance_javaw.exe_minecraft.exe.heapdump -Xss1M -Xmx2G -XX:+UnlockExperimentalVMOptions -XX:+UseG1GC -XX:G1NewSizePercent=20 -XX:G1ReservePercent=20 -XX:MaxGCPauseMillis=50 -XX:G1HeapRegionSize=32M
Fabric Mods:
apoli: Apoli 1.0.3
artisanat: Artisanat 2.1
calio: Calio 1.0.1
cardinal-components-base: Cardinal Components API (base) 3.0.0
cardinal-components-entity: Cardinal Components API (entities) 3.0.0
cloth-basic-math: Cloth Basic Math 0.5.1
cloth-config2: Cloth Config v5 5.0.38
dawn: Dawn API 2.0.5
enchant_giver: Enchant Giver 1.1.0
fabric: Fabric API 0.37.2+1.17
fabric-api-base: Fabric API Base 0.3.0+a02b446313
fabric-api-lookup-api-v1: Fabric API Lookup API (v1) 1.2.0+2b5c62d018
fabric-biome-api-v1: Fabric Biome API (v1) 3.1.11+c345aea818
fabric-blockrenderlayer-v1: Fabric BlockRenderLayer Registration (v1) 1.1.5+a02b446318
fabric-command-api-v1: Fabric Command API (v1) 1.1.3+5ab9934c18
fabric-commands-v0: Fabric Commands (v0) 0.2.2+92519afa18
fabric-containers-v0: Fabric Containers (v0) 0.1.12+a02b446318
fabric-content-registries-v0: Fabric Content Registries (v0) 0.2.4+2e8bd82f18
fabric-crash-report-info-v1: Fabric Crash Report Info (v1) 0.1.5+be9da31018
fabric-dimensions-v1: Fabric Dimensions API (v1) 2.0.11+6cefd57718
fabric-entity-events-v1: Fabric Entity Events (v1) 1.1.0+a02b446318
fabric-events-interaction-v0: Fabric Events Interaction (v0) 0.4.9+a722d8c018
fabric-events-lifecycle-v0: Fabric Events Lifecycle (v0) 0.2.1+92519afa18
fabric-game-rule-api-v1: Fabric Game Rule API (v1) 1.0.7+6cefd57718
fabric-item-api-v1: Fabric Item API (v1) 1.2.4+a02b446318
fabric-item-groups-v0: Fabric Item Groups (v0) 0.2.10+b7ab612118
fabric-key-binding-api-v1: Fabric Key Binding API (v1) 1.0.4+a02b446318
fabric-keybindings-v0: Fabric Key Bindings (v0) 0.2.2+36b77c3e18
fabric-lifecycle-events-v1: Fabric Lifecycle Events (v1) 1.4.4+a02b446313
fabric-loot-tables-v1: Fabric Loot Tables (v1) 1.0.4+a02b446318
fabric-mining-levels-v0: Fabric Mining Levels (v0) 0.1.3+92519afa18
fabric-models-v0: Fabric Models (v0) 0.3.0+a02b446318
fabric-networking-api-v1: Fabric Networking API (v1) 1.0.13+2e8bd82f18
fabric-networking-blockentity-v0: Fabric Networking Block Entity (v0) 0.2.11+a02b446318
fabric-networking-v0: Fabric Networking (v0) 0.3.2+92519afa18
fabric-object-builder-api-v1: Fabric Object Builder API (v1) 1.10.9+b7ab612118
fabric-object-builders-v0: Fabric Object Builders (v0) 0.7.3+a02b446318
fabric-particles-v1: Fabric Particles (v1) 0.2.4+a02b446318
fabric-registry-sync-v0: Fabric Registry Sync (v0) 0.7.10+e2961fee18
fabric-renderer-api-v1: Fabric Renderer API (v1) 0.4.4+5f02c96918
fabric-renderer-indigo: Fabric Renderer - Indigo 0.4.8+a02b446318
fabric-renderer-registries-v1: Fabric Renderer Registries (v1) 3.2.0+a02b446318
fabric-rendering-data-attachment-v1: Fabric Rendering Data Attachment (v1) 0.1.5+a02b446318
fabric-rendering-fluids-v1: Fabric Rendering Fluids (v1) 0.1.13+a02b446318
fabric-rendering-v0: Fabric Rendering (v0) 1.1.2+92519afa18
fabric-rendering-v1: Fabric Rendering (v1) 1.7.0+2e8bd82f18
fabric-resource-loader-v0: Fabric Resource Loader (v0) 0.4.8+a00e834b18
fabric-screen-api-v1: Fabric Screen API (v1) 1.0.4+155f865c18
fabric-screen-handler-api-v1: Fabric Screen Handler API (v1) 1.1.8+a02b446318
fabric-structure-api-v1: Fabric Structure API (v1) 1.1.13+5ab9934c18
fabric-tag-extensions-v0: Fabric Tag Extensions (v0) 1.1.4+a02b446318
fabric-textures-v0: Fabric Textures (v0) 1.0.6+a02b446318
fabric-tool-attribute-api-v1: Fabric Tool Attribute API (v1) 1.2.12+b7ab612118
fabric-transfer-api-v1: Fabric Transfer API (v1) 1.0.0+3fe3c3f518
fabricloader: Fabric Loader 0.11.6
fallflyinglib: FallFlyingLib 3.0.0-beta.2
gateofbabylon: Gate Of Babylon 1.5.0-1.17
impaled: Impaled 1.0.1
ironchest: Iron Chests 1.2.0+fabric-1.17.1
jankson: Jankson 3.0.1+j1.2.0
java: OpenJDK 64-Bit Server VM 16
libcd: LibCapableData 3.0.3+1.16.3
libgui: LibGui 4.1.5+1.17.1
libninepatch: LibNinePatch 1.1.0
mavm: More Axolotl Variants Mod 1.0.3a
mcdw: MC Dungeons Weapons 3.4.1
medievalweapons: Medieval Weapons 1.1.7
minecraft: Minecraft 1.17.1
moborigins: Mob Origins 1.6.0
origins: Origins 1.0.2
origins-classes: Origins: Classes 1.2.2
playerabilitylib: Pal 1.3.0-nightly.1.17-rc1
reach-entity-attributes: Reach Entity Attributes 2.1.1
terraform-shapes-api-v1: Terraform Shapes API (v1) 1.0.4
worldedit: WorldEdit 7.2.6+4b2d1e7
Launched Version: fabric-loader-0.11.6-1.17.1
Backend library: LWJGL version 3.2.2 build 10
Backend API: NO CONTEXT
Window size:
GL Caps: Using framebuffer using OpenGL 3.2
GL debug messages:
Using VBOs: Yes
Is Modded: Definitely; Client brand changed to 'fabric'
Type: Client (map_client.txt)
CPU:
#@!@# Game crashed! Crash report saved to: #@!@# C:\Users\admin\AppData\Roaming.minecraft\crash-reports\crash-2021-10-03_09.58.22-client.txt
09:58:22.458
Process crashed with exit code -1

Update to the latest fabric api version :)
https://www.curseforge.com/minecraft/mc-mods/fabric-api