[AC Question]

My roommates Gmail account is attached to my Gmail account.i don't want here account synced with mine,because she can receive and view my private information.i want to know how to remove it?or separate them so I have my own account and she has hers?

[sfoLAX]

Hello. Do you mean you both have each others Gmail / Google account on each others devices. Just two Gmail accounts on an email / Gmail app.
You can have separate users on one device.
You can un check all her account sync settings. (Settings - Accounts - Google, open account name) or: Gmail - hamburger icon, tap account name - Manage accounts, eh 3 dot menu.

[Rukbat]

In short, you can't both have and not have her email (any email account including Gmail) on a single device and not on that device. If she receives her email on your phone/tablet, both of you can read both email accounts.

About the only way out is to inatall another email app, put one account on the app you have now, the other account on the new app - and get an app-password program, so each of you can only open the email app for your own email.