what is 2|1 live game means ?

Hi,

I am new to chess.com

I am playing 1 min and 10 mins chess games. I also see there is an option like 2|1 game under, play->live game.

what is this option mean? 

Its a 2 minutes game, with a 1 second increment.  The increment adds 1 second to your time if you premove.  

Sorry for asking dumb questions, but what is Premove ?

No need to apologize.  Pre-move is an option in Live Chess where you can make your move even when it is your opponents move.  

This is something that has been bugging me.  How do you do this pre-move thing?

I am often in situations in Bullet where I try to move as fast as I can, but I am reduced to waiting for the opponents move (when I know what it's going to be) before moving myself.  

Incorrect, you get 0.9 seconds for every premove.

Hi aynKaleem,

I am also relatively new here. From what I have seen so far, the time each player has in a 2 minute game increases as they play on once the king has moved. Please let me know if this is what you also experience. 

Mark

Both the website and app have a Live setting to enable premoves. Your premoves should be displayed in red until your opponent moves. See link.
https://support.chess.com/customer/portal/articles/1444864