As you know the cutoff varies every year and as you didn't mentioned about your domicile we can't say about it. As every time the seats are categorised into 85% state quota and 15% all in india quota.

You should get maximum of 550+ marks for the safer side and to get into the government medical colleges.

You can check the link below for the knock out neet.

https://learn.careers360.com/knockout-neet-may

You can comment below for further queries.

All the best..!