Replace my old iPhone 7.

How what? Determine what phone you want, determine the cost, then go to an Apple store and trade in your phone for a new one. You will get some credit for your old phone. You will still have to pay for a new phone. You can’t get one free.

No one here will give you a free phone. You can trade your phone at an Apple Store and buy a newer phone.

Go to an Apple store and buy a new phone.

That's not going to happen.