>>532350846
You can try making some simple textures and then using this tool on github to bring them into a 3d-looking space:
https://cpetry.github.io/NormalMap-Online/

>>532350942
Do you mean in photoshop or modeling a single strand of hair in 3d? If it's photoshop, one good starting point is to apply a Oil Painting filter to hair. Then, just draw a few hairs yourself and play with the blending modes to get results you like. Layer by layer.