How can I add Username field? when I create a user I want to add more fields on the create user section and make him login by email or username

Have a look into the

UsernameIsEmail

setting https://docs.umbraco.com/umbraco-cms/reference/configuration/securitysettings (true by default, sounds like you want to set it to false).

@Sebastiaan Thank you bro, But how can I add more fields ? like contact number or more personal info?

Backoffice users don't have custom fields, you'd be looking at 3rd party identity providers if you want to add more info.