Alright, so I want to preface this with telling you I love this mod, it adds such an amazing beginning to the game. I want to help you make this mod meet it's potential since it is really good, which begins with giving you pointers on the grammar within.

Item Names:
-The item names within have capitalization errors. For example, "Antler pickaxe" should be "Antler Pickaxe". This applies to each item in the mod.
-Drought Grass should be Dried Grass, and Drought Grass Bed should be Dried Grass Bed.
-Animal Feeder should be Feeding Trough
-Aquaduct should be Aqueduct

Mob Names:
-Same thing as the situation above, but for mobs. "Woolly Rhino", and "Saber-Tooth Tiger".

Stone Tablet:
(Front Page)
-Intro could be "Welcome to the manual for Stone Age! If you find any bugs within this manual or mod, please report them on Github."
-Weapons and [T]ools
-Armor (remove the s, armor is plural)
-Food (remove the s, food is plural)
-Making [F]ire

(Blocks Page)
-Same capitalization changes as items and mobs
-Wooden and [Stone] Slabs

(Flint Workbench Page)
-"This workbench allows you to craft primitive items. You just have to arrange the required items on the workbench with right-click, and then right-click with the flint knife to craft the item."

(Drying Rack Page)
-"The drying rack is used for drying items like grass. Just right-click the drying rack with an item and wait. Note that the item is only dried during the day."

(Tanning Rack Page)
-"The tanning rack is used for tanning raw hide into leather. You can place raw hide on the tanning rack with right-click and then right-click on the hide several times with a flint knife."

(Stone Chest Page)
-"The stone chest allows you to store a small amount of items. It is still better than nothing!"

(Tree Stump Page)
-"The tree stump is a way to get planks of half-slabs. You can just place a valid item on the tree stump with right-click and then left-click with the required tool; an axe for wood, or a hammer for stone."

(Aqueduct Page)
-"The aqueduct allows you to transfer water to hydrate your crops. To fill the aqueduct with water, place one near a water source block. You can activate the aqueduct with a right-click, which will result in bubbles from it. Aqueduct can transfer water horizontally and downward. Activated aqueducts also speed up crop growth."

(Dried Grass Bed Page)
-"Due to wool being unavailable to you, you can still sleep on a bed made from dried grass."

(Feeder Page)
-Rename Animal Trough
-"The animal trough feeds animals nearby. You can right click the trough to open the menu and place feed inside for your animals, such as wheat or seeds. An animal trough with food inside will speed-up the growth rate of baby animals and cause adult animals to breed."

(Millstone Page)
-"The millstone is used for milling wheat into flour, and sugar cane into sugar. Right-click while sneaking to open the menu, and place wheat or sugar cane inside. Then you can right-click the millstone with an open hand to mill these items."

(Campfire Page)
-"The campfire is used for cooking food."

(Crafting Table Page)
-"The vanilla crafting table is the final step to finish the stone age."

(Furnace Page)
-"The vanilla furnace."

(Hay Bale Page)
-"A hay bale can be placed under a campfire for more smoke."

(Fishing Net Page)
-"The fishing net allows you to passively catch fish by placing a grass mesh into it. The fishing net must be placed in water to function."

(Raw Hide Page)
-"Raw hide is dropped by deer, aurochs, mammoths, woolly rhinos, and cows. Raw hide can be tanned into leather using the tanning rack."

(Antler Page)
-"Antlers are dropped by deer. It is used for making tools."

(Unlit Torch Page)
-"An unlit torch can be lit by right-click on a fire, campfire, or another torch."

(Bone Arrow Head Page)
-"Bone arrow heads are used for crafting arrows."

(Dried Grass Page)
-"Dried grass is used as a crafting item and for making fire."

(Leather Strip Page)
-"Leather strips are used for crafting."

(Fish Bone Page)
-"Fish bones are dropped by fish and are used for crafting."

(Flour Page)
-"Flour is used for making bread dough."

(Mammoth Tusk Page)
-"Mammoth tusks are dropped by mammoths."

(Saber-Tooth Teeth Page)
-"Saber-Tooth teeth are dropped by saber-tooth tigers."

(Woolly Rhino Tusk Page)
-"Woolly rhino tusks are dropped by woolly rhinos."

(Backpack Page)
-"Backpacks can be used to increase your carrying capacity. Right-click the backpack to open it's inventory."

(Lead Page)
-"Leads are used to leash animals and lead them around."

(Leather Page)
-"Leather is made on a tanning rack. Right click the rack with a raw hide and then right-click multiple times with a flint knife."

(Sugar Page)
-"Used as a crafting item."

(Grass Mesh Page)
-"The grass mesh is used in a fishing net. It has 15 uses before it breaks."

(Antler Sickle Page)
-"The antler sickle is used for gathering grass."

(Flint Knife Page)
-"The flint knife is your first weapon. It's not very efficient, but it will help you survive and hunt animals. It is also used for crafting items on the flint workbench and for tanning."

(Flint Spear Page)
-"The flint spear is a ranged weapon which is similar to the trident, but less efficient. It is still very useful for surviving and hunting in the wild."

(Armor Page)
-Rename Leather Chestplate to Leather Tunic
-Rename Leather Helmet to Leather Cap
-Rename Leather Leggings to Leather Pants

(Fat Page)
-"Fat is dropped by aurochs, boars, deer, mammoths, mouflons, saber-tooth tigers, woolly rhinos, cows, pigs, and sheep."

(Venison Page)
-"Venison is dropped by deer."

(Fowl Meat Page)
-"Fowl meat is dropped by fowl."

(Auroch Meat Page)
-"Auroch meat is dropped by aurochs."

(Mouflon Meat Page)
-"Mouflon meat is dropped by mouflons."

(Boar Meat Page)
-"Boar meat is dropped by boars."

(Mammoth Meat Page)
-"Mammoth meat is dropped by mammoths."

(Rhino Meat Page)
-"Rhino meat is dropped by woolly rhinos."

(Tiger Meat Page)
-"Tiger meat is dropped by saber-tooth tigers."

(Auroch Page)
-"An ancestor of cows, aurochs must be bred for several generations before they are domesticated as cows. Aurochs are passive until attacked, after which all aurochs nearby will attack you."

(Boar Page)
-"An ancestor of pigs, boars must be bred for several generations before they are domesticated as pigs. Boars are passive until attacked, after which all boars nearby will attack you."

(Deer Page)
-"Deer are skittish, and will flee if you get too close. They are the only source of antlers, which are used for crafting your first tools."

(Fowl Page)
-"An ancestor of chickens, fowl must be bred for several generations before they are domesticated as chickens. Fowl are passive until attacked, after which all fowl nearby will attack you."

(Mammoth Page)
-"Mammoths are large, strong beasts. They are passive until attacked, after which all mammoths nearby will attack you."

(Mouflon Page)
-"An ancestor of sheep, mouflons must be bred for several generations before they are domesticated as sheep. Mouflons are passive until attacked, after which all mouflons nearby will attack you."

(Saber-Tooth Tiger Page)
-"Saber-Tooth Tigers are large, dangerous beasts. They hunt down smaller prey such as deer, fowl, and you."

(Woolly Rhino Page)
-"Woolly rhinos are passive until attack, after which all woolly rhinos nearby will attack you."

(Making Fire Page)
-"Drop dried grass on the ground, and right-click on it with a stick in each hand to start a fire."

I hope this helps!

Thank you for complete translation! This really helps.

Fixed in next release