Hello Aspirants,

Yes.As you have a rank below 1000, you can apply to all B category colleges and that includes Andhra University - [AU], Visakhapatnam.Especially since you have a rank of 300, you have high chance to get seat in AU.

Apart from Andhra University, below are other good colleges you can apply for:
Velagapudi Ramakrishna Siddhartha Engineering College - [VRSEC], Vijayawada
Dr. Lankapalli Bullayya College, Visakhapatnam
Annamacharya Institute of Technology And Science - [AITS], Kadapa
Lakireddy Bali Reddy College of Engineering - [LBRCE], Krishna.

Admission possibilities depends on the number of seats available, number of applicants, category ,overall rank etc.

You may see the various cutoffs in the below link:

https://www.google.com/url?sa=t&source=web&rct=j&url=https://bschool.careers360.com/articles/ap-icet-cutoff/amp&ved=2ahUKEwiJ6Iy3rq3uAhUvG6YKHVimBmoQFjAAegQIAxAC&usg=AOvVaw0uMDvMlbaNl-mst44w2_DR&ampcf=1

All the best