Managing personal Outlook.com account settings, security, and privacy
Make sure your password is long, complex and unique. It's best to use a password manager to create and remember it for you. Enable two-factor authentication or passkeys. After changing your password, visit https://account.live.com/proofs/manage, slide down to the "Sign out everywhere" Section and click the link there to log everyone out of your account. Visit https://outlook.live.com/mail/options/general/timeAndLanguage/regional to make sure the language is what you want it to be.