Please see the articles below on how to setup Multifactor Authentication on your phone:
First time setup- How to setup MFA using the MS Authenticator App
First time setup - How to setup MFA using a single device(phone)
How to change your MFA Method
Prefer not to use a cell phone? Here is information on YubiKeys
If you need any assistance with MFA setups and management, please feel free to reach out to the Tech Support team at 515-965-7300