about gate bt coaching

hello sir, 
1. plz can u suggest me there is need of gate bt coaching classes.if yes then which is best online or offline, suggest me some options or coaching names. 
because of im very poor in math im really get confused to joining coaching or not. 
plz give me answer fast becz batches almost started and till i have confusion. 
 2.and also suggest me some name of books lke arihant ...and all that ..etc. 
which is the best for studing