Hey,
First off,be sure of your calling. Just decide on what you actually want to do. If you wish to go for Bachelors in Commerce(B.Com Honours or B.Com Programme),the universities like Delhi University,Mumbai University and several others don't conduct entrance exams. You can directly get into them on the basis of your 12th boards examination.
If you want to switch to other streams also like Humanities,admission is generally through 12th marks in most of the colleges while some do conduct entrance exams
If you wish to go for BBA then,some colleges conduct entrance exams like DU JAT,GGSIPU CET BBA,NPAT BBA SET.
Hope this helps.
Good luck.

Hi ,

You can start preparing for BBA/BMS/B.com entrance exam if you are planning to pursue commerce further on after 12th. Apply for BBA entrance exam for private Universities like Symbiosis, Christ, DUJAT, BHU. 

for preparing for entrance exam you can prefer joining 2 months crash courses from T.I.M.I.E.S, pratham or edumentor. These institute help students in preparation for the various entrance exams after 12th.

That depends...well..what you want to do....if you are intrested in giving CA than you must prepare for it ..or if you want to do something else than prepare for it try to research about it and try to find best collages ..