PROBLEM 1:

When I set a lock screen, a Remote unlock agreement appears

SOLUTION 1:

By using Remote unlock in Find My Mobile, you can control your phone remotely in a secure state if you forget how to unlock your screen. To use this function, you must agree to store your encrypted PIN, Pattern, or Password information in the Find My Mobile server. Google new security policy for Pie OS does not allow Remote unlock via Find My Mobile without use of a PIN, Pattern, or Password.

You can enable Remote unlock from your device by navigating to Settings, and then tapping Biometrics and security. Tap Find My Mobile, and then tap the switch next to Remote unlock.

Note: Find my mobile is not available on all carriers.