To get admission in BITs, you will have to crack BITSAT exam as this is the only way possible to get seat there and as per the eligibility, you will have to get 75% aggregate in PCM and 60% should be there in individual subjects. 

To check the complete eligibility, you can go through the below link-

https://engineering.careers360.com/articles/bitsat-eligibility-criteria

Also, the application forms are going on so if you re interested and eligible then you can apply -

https://engineering.careers360.com/articles/bitsat-application-form

Good Luck!!!