Hi there!
It actually depends on the domain of the email address you are using. If your domain ends with @hotmail.com, @live.com, @outlook.com, or @msn.com then your account is being managed by Microsoft.
If it is not part of the domain mentioned above then your provider is a different company or email provider. Just go to your providers website to update your password, you might also need an app password which you can create on your providers website. The app password can be used when signing in on your Outlook mail application or mail apps. The app password usually is needed if you have 2FA or 2 factor authentication enabled on your account.
I hope the additional details helps.