Hello Aspirant,

You don't require a gap certificate for this.

You need

1. Acknowledgment Form from APOnline / TSOnline center Or Debit Card / Credit Card / Net Banking details - For payment of application proof.
2. Hall ticket Number of the last passing exam.
3. Marks Memo / Hall Ticket Number of Intermediate / 10+2 / Equivalent
4. Subject pertained to Engrg (E), Agri & Medical (AM) (or) both(E & AM) Eligibility norms fulfilled furnished in the TS EAMCET website.
5. Birth Certificate / SSC (or) Equivalent Certificate for DOB.
6. For the Regional category (OU / AU / SVU / Non-Local)  The regional nominee statement is handed out by MRO (or) authorized department.
7. Annual Income of Parents ( Below 1 Lakh, 1 Lakh, and Above,  Below 2 Lakhs and 2 Lakhs and Above) The earnings statement is handed out by MRO or equivalent authority.
8. Study Details  - Study records from  1st standard to Intermediate / 10+2 / Equivalent
9. Aadhar proof
10. Caste or EWS certificate if required.

I hope it helps.