The documents required mandatorily are:

NEET Rank Card

SSC Marks memo

12th marks memo

Study certificates from 6th to 10th

Study certificates from 11TH TO 12TTH

Latest Passport size photo

Specimen signature

Applicable documents are:

Transfer Certificate

Latest Caste certificate if applicable

Minority certificate for Muslims if applicable

EWS Certificate for the year 2019-20 if applicable

Latest Parental income if applicable

NCC Certificate if applicable

CAP Certificate if applicable

PMC Certificate if applicable

Anglo Indian Certificate if applicable

Residence Certificate

Aadhar Card

So you do not need GAP certificate. For more information, please read the prospectus available at: http://www.knruhs.telangana.gov.in/sites/default/files/2020-10/MBBS%20BDS%20PROSPECTUS%202020-21.pdf