Hello,

you should follow the prescribed books by the AP PGECET. Study materials is hard to get. i would suggest you to search in your browser. There are private webpages who provides study material for different branch like manabadi webpage

You can also get previous year paper to solve it yourself and know how questions are asked. You can also appear mock test which is available in the official webpage of AP PGECET @ https://sche.ap.gov.in/pgecet/PGECET/PGECET_HomePage.aspx

to practice mock test and syllabus structure, please visit the link below:- https://engineering.careers360.com/articles/ap-pgecet-syllabus

Hope it helps!