I forgot my long in password for my MacBook air

See the following Apple articles:

Reset your Mac login password

https://support.apple.com/en-mn/guide/mac-help/mh35902/mac

Sign in with your Apple ID

Sign in with your Apple ID - Apple Support

Sign in to your Apple ID preferences on Mac

Sign in to your Apple ID preferences on Mac – Apple Support (UK)

If you forgot your user or account name on Mac

If you forgot your user or account name on Mac – Apple Support (UK)

Change the login password on Mac

https://support.apple.com/en-gb/guide/mac-help/mchlp1550/mac

If you forgot your Mac login password

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