You only need one Apple device. The two factors are your password and the verification code from a trusted device (or trusted phone number).
See information in Two-factor authentication for Apple ID - Apple Support
and Get a verification code and sign in with two-factor authentication - Apple Support
I would highly recommend having more than one trusted phone number. They can be Androids, landlines, friends or relatives.
To turn on two-factor, see the "Turn on two-factor authentication for your Apple ID" section of Two-factor authentication for Apple ID - Apple Support
To add trusted phone numbers, see the "What is a trusted phone number?" section of that same support article.