Not Enough Default minecraft models

Hey McCreator! Just recently I started to make a mod for a rp on my youtube channel. Everything was going perfectly until I wanted to add in a normal Minecraft cat model for a mob I wanted to create. I looked through and well no cat models. So, like a normal person, I looked around and found nothing apart from "download a software". I know NOTHING about 3d modeling and others, like me, have the same problems with there just not being enough models. Hopefully you address this serious issue that there's just not enough default Minecraft models. Thanks.