>>307052508
Try an MMD model if you want to start learning more in depth avatar work. As the other anons said, they're easy to fix up for vrc so provide a good learning opportunity. You can find models on 3d.nicovideo.jp, bowlroll, mmda booru, and more. 

An alternative is buying a booth model. These come with a prefab you can pretty much just drag and drop into a scene ready to upload.