2 step authentication

I’m relatively new so I want to apologize ahead of time if this is in the wrong forum channel.

I’m looking into adding 2 step authentication to my app.

Some slick executions of this I’ve seen include sending a one time email code or using something like Google Authenticator or Authy.

On the surface, I think it would be simplest to generate a one time key upon initial login, save to DB and set an expiration on it (now +1 hour for example), email it to the user and only allow the user to proceed into the app if the key they entered matches the generated key.

I would love to hear any insight into whether anyone has done any sort of 2 step authentication and whether there is a preferred/recommended Wappler method.