By the name of the mod, you probably already knew that it will allow you to gain experience for the harvest in Minecraft.
XP From Harvest Mod for Minecraft 1.15.2/1.15/1.14.4
Now just harvest as usual and you will receive a small amount of experience for this. The mod is extremely fair as it will give you more options.
1.15.2 – XPFromHarvest_1.15.2_1.2.0
1.14.4 – XPFromHarvest_1.14.4_1.2.0