You should have a good rank to get a free seat in EAMCET colleges. Now the good rank can be the best that you can achieve but always try to have a rank <10,000 to have the best probability of getting a seat. Now also the category matter and you didn't mentioned any. If you are from a UR category then try to focus the best you can do and a rank <8000. This figures may seem tough to you but to have a higher certainty you have to work hard.

I hope my answer helps. All the very best for your future endeavors!