which branch can i get with 80 marks in jee at AIT?

There are very less chances to get into AIT pune with JEE Main score of 80 marks. With 80 marks in JEE Main your rank would definitely be more than 2,00,000. And following are the closing ranks for different categories for AIT Pune:

Computer Engineering              55132

Elec. and Telecomm. Eng.         87857

IT                                                    65295

Mechanical Eng.                          111326

And these are far away from your expected rank. So, try to improve your score and improve your chances to get into AIT Pune.