Hello, Identity Experts

I have some requirements to implement SMS-based and authenticator app MFA for community.

Here is the requirements.

1. SMS-based MFA after username and password authentication for community user if the user has mobile phone number.

2. Need to implement authenticator app MFA for community if the user doesn't has mobile phone number.

I think, I have to implement it in Apex to meet these requirements.

I've read the document below, but I don't know how to implement it in Apex.

https://help.salesforce.com/articleView?id=sf.security_2fa_apex_config.htm&type=5

Where can I get the sample code?

I will buy identity verification credits for SMS-based MFA.