Hello aspirant!  if you participate in second phase counseling your first phase alloted seat will be reserved. If you get another branch or college in second counseling you will get there but if no seat will be alloted to you in second phase anywhere you can automatically go your first phase alloted seat.

Hello student The moment you apply for second round your first round seat got cancelled itself so make sure what you're doing is good for you or not do a proper research and then apply for second round.

Feel free to comment if you have any doubt 

Good luck