Shoe's are simple :

With whatever shoes/boots you get on your hands, bought or free?? Keep the obj file and the texture, delete all the rest. Load the obj in Blender, cut it up, adapt, regroup, and reweld, around the figure you choose, export and give it a run in the fitting room. => Done.

99% what's available is ***** "fill in the blank". Like the extreme high heels above? Probably great work but every day usability is as good as taking the kids to school in an aircraft carrier. LOL.