Wet Milling is also known as wet sieving and as the name indicates wet milling is the process where we break down the large lumps of the wet mass to reduce the particle size...

The process of mixing the fine powders with solvent/binder solution,slurry or paste in a high shear or low shear mixer is known as kneading..

Wet granulation is the size enlargement process where the fine powder particles are brought closer or are agglomerated with the help of binders &  granulating fluid like water or IPA to form large, strong & permanent structures known as granules...

Did you ever think why do we use the granulation process instead of using powders directly for compression?