Creating a local user account allows someone to use your PC without a Microsoft account. Follow these steps to add a new user in Windows 10.

Via Settings

Go to Settings > Accounts > Family & other users and click Add someone else to this PC. Choose I don't have this person's sign-in information, then Add a user without a Microsoft account.

Via Command Prompt

net user NewUsername StrongPassword /add
net localgroup Administrators NewUsername /add