Hi Josephine1956,
Congratulations on your new MacBook Air. Are you attempting to enter the login password associated with your Mac or the Apple ID password? You can view instances of when you may be asked for your login password in the information below, from the article here: If Touch ID isn't working on your Mac - Apple Support
"If you need to enter your password
The first time you log in after you turn on, restart, or log out of your Mac, you must log in by entering your password manually. After that, you can use Touch ID to log in.
Additionally, you might need to enter your password instead of using Touch ID in these situations:
- Your fingerprint isn't recognized five times in a row
- You haven't unlocked your device in more than 48 hours
- You're trying to change settings in the Touch ID & Password pane of System Preferences"
If this is related to the Mac login password, check out the information and steps here: If you forgot your Mac login password and here: Reset your Mac login password
Cheers.