i keep getting pop ups saying sign in required! is it a virus?!!

No, data will this be on iCloud. Once you log in again and toggle on iCloud Photo, iCloud Drive etc, they'll show up again.

But you should still back up your phone to make sure you don't lose anything: How to back up your iPhone, iPad, and iPod touch - Apple Support

Hi,

No it's iCloud. Just sign-in.

If it ever ask multiple times again although you did sign in, try to this: https://www.imore.com/ios-help-how-fix-repeat-icloud-sign-requests-iphone-and-ip ad