As an admin, you can turn off multi-factor authentication. I’ve put this together specifically for people who might have signed up for a Microsoft 365 trial (which I’ve outlined in a previous post), or perhaps you’ve set up a tenant to run training. With MFA off, users wont be prompted to provide a phone number or another authentication method when trying to sign in to their Microsoft Tools.
Go to the Azure Portal https://portal.azure.com/#home and sign in with the admin account for your organisation. Click on the hamburger icon to expand the menu and select Azure Active Directory.
Select Properties from the left navigation menu.
Click Manage security defaults, and toggle NO for Enable security defaults. Select your reason for disabling the security defaults, then click Save.
MFA will now be turned off.
Rishona Elijah 
What’s the benefit of turning it off? Can I login with password only? Using OTP with office mail every time is so uncomfortable. Thanks.
Yes, if you turn it off, you’ll just need your password to sign in. It wont ask you to use the authenticator to approve the sign in.