How can I recover my Apple Account on iPhone 7?

Accounts are not specific to particular devices. There is no "iPhone 7 account", there is just an Apple Account which is also signed into the iPhone 7.

What do you mean by "recover"? What happens when you just try to sign into it? Have you tried signing into iCloud.com with a web browser using a computer? If you see error messages, we need to know exactly what they say.

geezy34 wrote:

How to retrieve my iPhone 7 account

It's not clear what you are trying to say.

Were you using a different Apple ID (Apple Account) on the iPhone 7 than you are now on the iPhone 12 shown in your tag line?