The possibility of getting the govt. seats in your case is difficult considering you in the general category. The govt. seat demands 500 or more marks for the medical courses. Also the number of seats you have mentioned are not 800 there more seats if talk about the all india seats for the medical branch. RBA certificate is applicable if you have any particular cast reservation in your state or there is no provision for this RBA certificate in NEET admissions. The simple thing is that if you belong to any reserved category then you can apply through the reserved quota seats else you have to apply through the general seats quota. The counselling rounds will decide the possibilityt of the admission in the college. A link is given below where you can find out the cutoff marks for the various govt. colleges in medical and dental field so that you can check the possibility if any.

https://medicine.careers360.com/articles/neet-cut-off-for-government-colleges