Customization question

[Zexis332]

Hi, I just wanted to ask if there was a way to edit the model and or texture through blockbench and if so how would I add or change the files necessary to do so.
I am soon to be opening a small server for a bunch of my friends and had the idea of using your mod but wanted to add new customizations to the werewolf form such as adding textures that look like my friends characters, that way the server feels more personal.
is there a way to add more to the customization menu?