What will be the cutoff for mbc to get private government seats 

Yes, you are eligible for NEET exam make sure you fulfill other eligiblity criteria as well i.e you should have aggregate 50% marks in PCB for general category.

There is a relaxation of marks for reserved category.

Your minimum age should be 17 years and it should be not more then 25 years for general category.

To apply for the application form you can refer below link

NEET 2018 Application Form

Good Luck!!