Will restoring my old iPhone 6s from my iPad delete my iPhone 14 Pro backup?

I had an iPhone 14 Pro that was lost/stolen and I'm currently waiting for the replacement device to be shipped. I have my wife's old iPhone 6S that I erased. My plan was to restore the 6S with the back-up from my 14 Pro and use the 6S until my new 14 Pro arrives. When I tried to restore from the backup, it only gave me the option to restore the 6S from my iPad mini becuase the IOS on my 14 Pro is not supported by the technology in the 6S. My question is this: if I choose to restore the 6S from the iPad, will I later be able to restore my new 14 Pro with the back-up that was previously created by my 14 Pro? Or will the new 14 Pro restore from the 6S?

Thank you for any and all help