I have just bought my macbook air m2 and i forgot the password

Apple Silicon M1 / M2 Computer 

1 - Choose Apple menu > > Shut Down.

2- Do not  attempt a Restart to access this feature. The computer Must be Shutdown and pause for about 10 seconds before moving forwards 

 3 - Press and hold the power button on your Mac until you see “Loading startup options.”

4 - Click Options, then click Continue. 

5 - Top Tool Bar >> Utilities >> Terminal

6 - Type resetpassword as one word and no spaces

7 - Press Return key

8 - Follow the prompts and remember the New Password

See the following Apple Support article for information on a forgotten Mac login password: https://support.apple.com/en-us/HT202860