iPhone Data and App Transfer From SE (2020) to 15 Pro Max

With a refurbished iPhone 15 Pro Max 256GB, there were complications when transferring data and apps over from my old phone, an SE (2020) 64GB. The first attempts were unsuccessful due to updating and then upgrading to iOS 18.1. I backed out of the transferring, got the update and upgrading done to 18.1, then got my phone # transferred over with Mint Mobile, but now I need to go back to the SE and transfer all the pictures and docs and apps over to the 15. What's the best way to do that?