But Ma'am I have to apply through all india quota because I'm from Jharkhand..are there still good chances to get a seat?What could be the approx fee still can you tell

It might be difficult to get admission through the All India Quota, at this score. However, I would advise you to not rush and wait for the merit list to arrive. Post that, kindly wait patiently while your counseling is going on and very carefully fill in on your choices, that is a very crucial part.
I would also advise you to wait till the mop up round.
The fees may range from 50,000 per annum and may even go high till 8,00,000 per annum, depending on the college you choose.

And if I apply for Jharkhand state counselling then are the chances of getting seat fair?

Yes, you might get into a good college if you apply from state quota, as the number of seats are more. Every college has 85% seats reserved for State Quota students and only 15% seats for All India Quota.

Thankyou so much

Ma'am if the score is 324 ..are there still chances to secure private dental seat in Jharkhand?