Hi Car-Bor,
Thank you for using the Apple Support Communities.
It sounds like you’re having problems with signing in to your accounts on your Mac and we found some Apple Support articles that can help.
If you can’t sign in or use iCloud, follow these steps: If you can't connect or sign in to iCloud
If your Mac keeps asking for the login keychain password, follow these steps: If you need to update your keychain password on Mac
"If you need help with iCloud Keychain," follow these steps: If iCloud Keychain won't turn on or sync
If Mail keeps asking for your password, follow these steps: If Mail on your Mac keeps asking for your password
If the apps on your Mac don’t work as expected, follow these steps: If an app on your Mac stops responding, closes unexpectedly, or won’t open
Best regards.