Should I choose non attending shcool in +2 for JEE preparations?

@ vansh 
No , most of the student are doing wrong here only , join a good cbs schools , but u need to make up the mind that u have to spend less time in school prep and more time on jee prep . 
and that school will help you in jee prep also , cbse schools generally refer to ncert textbook , and in jee main the questions from organic and inorganic are lifted lines of ncert ., 
so, better join a school regular besic , and in that u will not be bored by studying also , and give the rest amount of time in jee prep . 

ALL THE BEST ..