Is Multi The Same As Two
Technically, no. The idea behind MFA got big when it became common knowledge that using text messages and cell phone numbers as a way to validate your identity was not nearly as secure. First, it is not impossible or even difficult to clone SIM cards, or steal phones. The idea is that many factors can be used to validate you are who you say you are.
What Does It Mean
If someone steals your passwords, or guesses them, or you tell them by accident, having MFA set up on sensitive accounts will save you because the bad actor will still not be able to log in without knowing this additional piece of information. I highly recommend you have MFA set up on your primary email address and major bank accounts. Other places are less critical, but better to be safe than sorry.
Authy
I use Authy as my MFA token store. This is an app that runs on your computer or phone (always have at least two devices, but keep allow multi device off afterwards, enabling it only to add a new device when you get a new phone or laptop and remove the old one). This app synchronizes all my MFA tokens (QR codes) across all my devices. I especially like that there is an Apple Watch app, so I rarely even have to pick up my phone when I am authenticating to a service. But if you don't have my phone in your hand, or my watch on your wrist, you won't get very far with my accounts. Twilio (parent of LastPass and Authy) suffered a hack in August 2022, and some Authy accounts were hacked (0.0001%) and LastPass obviously had some issues as well. I still think Authy is the best choice here (certainly over Google Authenticator). You could consider Duo or Okta Verify if you prefer.
Password Management
While not the exact topic, it's relevant and tangential. I use iCloud to store most of my passwords, and TouchID/FaceID to unlock everything, including passwords, where possible. Security-focused individuals would claim this is not very secure, and I respect that outlook, but I trade security for convenience, since I can use any device I log into iTunes with immediately for all services. And I still have Authy to hold my MFA tokens. Regardless of what you pick, pick something, and do not reuse passwords or try to keep passwords secure on your own (although KeePass, used properly, is fine, if you don't mind the hassle). BitWarden, 1Password, Keeper, and Dashlane are all viable services to use that should play nicely with whatever ecosystem you are currently using. The only service I would not recommend is LastPass, from a usability, reliability, and security standpoint, I do not believe they achieve passing marks in any of those areas.