When you open Windows 10/11 Mail for the first time you will see the following screen - click Get started to add your email accounts

 

 

If you are signed into Windows using a Microsoft Account then that email account will be added automatically for you

 

If that is your only email address then click Ready to go to access your emails

 

If you have other accounts to add then click Add account and follow the Mail Account Setup guide (from second step onwards)