Hello Aman,

Your 12 marks are not bad. And yes , definitely you can get direct admission in colleges for mechanical branch through management quota which is completely legal by gov of India for private colleges. 

There are lot of options of colleges which take direct admission, but I will advice you to take admission in Bangalore colleges as they can completely change your further career. The placement opportunities in Bangalore colleges is very high compared to other colleges in India . 

Colleges like RVCE, BMS, Ramaiah etc are awesome In  their placement. Even companies like Mercedes Benz, Maruti, Audi , Mahindra etc are visiting their campus for mechanical students recruitment . Hope you will take right decision.

For any query, ask me in comment section, or can call me 6388724381.