non authoritative client-server multiplayer game?

im wondering the performance of this type of set up
as far as i know, one player is acting as server and others as client
so will the player as server have an advantage than other players?
since other players have pings maybe 100ms,200ms

what would actually happens? will other player lags and the server player very smooth?

and 100ms,200ms ping playable for other player?

Non-auth will be smooth locally but not for the others. No matters if it’s server or not.

so should i let a player as server and others as clients?
or i host a server and others as clients ?
if a player as server, would his internet speed and location determine the lag of others?
if i host a server, others as clients to connect ,would internet connection be better?
if i host a server, how can multiple session be played at the same time?

In Unity a server can also be a player yes.

Keep it simple, have the users hosts servers if they choose to.

Yes and also the clients connections speed and location.

Impossible to answer.

Unity wasn’t made for this kind of setup. If you realy need this kind of setup you would be better off using a third party solution.