A good email provider should have two-factor authentication, or 2FA, as it enables them to verify the account owner by sending a special passcode to a mobile device. While most email providers offer two-factor authentication, you should check your TOS before using the service. Make sure that your messages are encrypted and protected against brute-force attacks, and that your
data is secure. If you're worried about your privacy, consider another alternative. Google, for example, allows third-party developers to read your emails.
See also -
https://emailspedia.com/how-to-encrypt-email/