The VG Resource

Google is often your friend with these types of things. Though if your program has a help option you may want to check that first. Generally they try to keep info like that pretty clear for the user.

Googling screws up for me, I search "add textures in fragmotion" and it gives me results for Blender for some reason. Help is equally useless, it talks about textures using UV Coords or something but doesn't tell me how to add textures.