Do I need rental car insurance?

If I just got auto insurance ?
NEED HELP FROM CALIFORNIA CITIZENS about car  insurance  !?
What auto-insurance is provided by corporations for students? I am an international student in Ohio. I'm more than 21. I am today looking to purchase automobile  insurance   and obtain a student's permit lately. I'm separate and may not be added to other folks's coverage. I've been looking the World Wide WebCHEAP CAR INSURANCE FOR 17-YEAR OLDS?
"I'm planning to be deploying soon and letting my partner while i'm gone to make use of my cars. I am just curious. Since she will be the principal driver can leave the registration within my name but have the insurance in hers