How to add contacts from recents?

I've searched Google, but like it was with my old Android phone, the suggestions given for my new iPhone 12 don't work.

1. I click "CONTACTS" with the Phone app.
2. I click the + sign at the top right corner.
3. Then I asked to add a lot of the person's info, but never am I given the opportunity from selecting a new number from a recent caller's number.

Please tell me iPhones are NOT like the Android phones with many different versions of the Android software out there.