I am trying to update my macbook air to mac monterey. I reset my password and it still is not letting me in.

Confirm you are using the password for that Apple ID. For example, the upgrade is not asking for your Mac's login password, which can be different.

To verify your Apple ID credentials are in fact correct, log in using them here: https://appleid.apple.com/

Then, confirm you are signed in to iCloud on that Mac. using those same credentials.  (Apple menu) > System Preferences... > Apple ID > Password & Security. If in doubt, click Overview then Sign Out...

Sign in again using your Apple ID and its password. That should do it.

Can you describe exactly where you're getting stuck? What is not letting you in?