Unity how to implement multiplayer with a 1-person view?

Question

Unity

I have a model with mixamo, I need to have only hands with the same animations from 1 person,
and I can see 3 faces from others with my whole body

Answer 1

https://unity.com/fps-sample
judging by the comments, you have more than one problem there, but just "how to do everything"
here is the link. there is a repository and explanations and a bunch of other useful things
, download and sit for another week (or maybe another month), looking at the documentation - rake what's in the demo and how it's done.
the network part and how to display the characters, etc. - you can definitely unearth and understand the principles there. and then look and repeat it will come out if you catch the essence)