Ciao, io ho 11 anni.
What should a 13 year old's chess rating should be?
I think chess rating isn't so much dependent of age, rather of the time one has spent on playing chess. It is additionally dependent on how much you want to learn chess and how much you actually do to learn chess.

15yrs old sorry
Probably only 3 or 4
Sorry for the confusion. I meant that there were probably only 3 or 4 people who became grandmasters at 15 years old or before

I say just enjoy the game, win or lose you both ways win, if a loss, if gained anything from, you win by that little gained knowledge of what not to do hopefully next time..

...the more your love FOR chess, the more you'll increase, as well the 4-player-chess here does increase your standard skills.

If I you have 1900 in rapid and just started then you must be a chess genius. People take years to reach that rating, did you play chess before?

If I you have 1900 in rapid and just started then you must be a chess genius. People take years to reach that rating, did you play chess before?
absolutely
I am 2000, but want to be a gm in the future.