Degree

You can refer the following link to get detailed information about some of the best B.Sc computer science colleges in Andhra Pradesh.
https://www.shiksha.com/science/colleges/b-sc-computer-science-colleges-Andhra-Pradesh.

Careers related to petroleum engineers:
*Architectural and Engineering Managers
*Chemical Engineers
*Civil Engineers
*Geological and Petroleum Technicians
*Geoscientists
*Industrial Engineers
*Mechanical Engineers
*Mining and Geological Engineers

To pursue B.Ed, you don't need any experience in teaching. After doing B.Ed, you will get a job as a teacher. And yes, 66% is enough to apply for B.Ed in IGNOU.
For more details regarding the admission process, follow the link given below:
https://www.shiksha.com/university/ignou-indira-gandhi-national-open-university-delhi-3030

What kind of courses you wants to pursue? As per rules, you can not do two or more courses at the same time because you will not be able to claim the benefit of other courses at the time of employment or higher studies. Because employers can asked the question regarding the course for which you are calming the benefits.

Top 5 colleges in Hyderabad to do degree in B.Sc computers:
St. Francis College for Women,
GITAM College of Science,
Nizam College,
St Ann's College for Women,
A. V. College of Art Science and Commerce

Colleges for B.Sc computer in Vijayawada, Andhra Pradesh are:
-Andhra Loyola College, Vijayawada Andhra Pradesh
-Maris Stella College
-Sri Durga Malleswara Siddhartha Mahila Kalasala
-SRR and CVR Government Degree College
-Saveetha Amravati University

Dr. Lankapalli Bullayya College
SRM University Amravati
GITAM institute of Science
KLU

You are not mentioned which group you had completed your 12th with? There are ample of groups for both groups. For BIPC, biotech group is best and for maths, computer science is trending.
All the best.