Im trying to modify your mod for personal use but came to the realisation that there is several classes missing in the Repository making it impossible to build the Mod

If you are building Fabric you have to exit the build.gradle, change:
https://github.com/tom5454/Create-Ore-Excavation/blob/main/Fabric/build.gradle#L187C1-L196C2
to

sourceSets {
	main {
		java {
			srcDir "../Forge/src/platform-shared/java"
		}
		resources {
			srcDir "../Forge/src/platform-shared/resources"
		}
	}
}

Ah thank you!