how do I restore iMessages from old iPhone to a new iPhone

Hi SummerStrands,

Welcome to Apple Support Communities. It looks like you were reviewing this article: Transfer data from your previous iOS or iPadOS device to your new iPhone or iPad - Apple Support Were you able to select one of the transfer methods? If not, you'll want to select one of those methods such as Quick Start, iCloud, iTunes or Finder to transfer your data which will include your conversation threads in the Messages app.

If you're unable to complete that process, please provide the community additional details of what you're experiencing when attempting to recover your messages.

Kind regards.