When trying to install OS Monterey, I am asked for my "Administrator password". When I enter my password from my applee account, the password is rejected. How can I log on?

Are there more than one User Account on this computer ? Is the Monterey upGrade being installed from an Administrator Account.

The installation will require being done from the Owner ( Administrator ) of this Computer

When you setup a mac for the first time you are asked to make a User/ account, this will by default be an Administrator account, which you selected a username and a username password, you would also have been asked to make a password hint.

To check your account status open System Preferences> Users & Groups. Click on Password

and in the left hand column you will see your username and its status it should be Admin if you

have changed it to Standard at some point, you shouldn't have but if you had you could be in

some difficulty.

This is the password your mac is wanting, not your AppleID password

If you cannot remember your Admin password then read this,

https://support.apple.com/en-gb/HT202860

Choose a password you are going to remember, write it down and hide it somewhere you will remember.

I want to upgrade to Monterey. When I enter my admin. password/id the system rejects it and I can't continue. What do I do?

Only one user account on this computer. I'm the only user, no administrator.

It wants your local admin account password, not your Apple ID password.