A:Answer Hi Sandy,
I just bought new SE's for my entire family and I liked the option to restore the new phone from a backup in iTunes, however there are three options on the Apple support page below. Just click on each method to launch the steps for each option.
https://support.apple.com/en-us/HT201269
Just to elaborate on my preference. I installed iTunes on my computer. (Windows for me, however iTunes should work the same on a Mac) Once iTunes is open I plugged in the older iPhone and followed the prompts to make a backup. I ran the backup twice to make sure. Once the backup was complete I removed the old phone and plugged in the new iPhone and powered it on, then followed the prompts on the phone. Below is a link to Apple support page for making a backup, two two methods are listed, Use your computer is my preference. It is often faster than the iCloud method.
https://support.apple.com/en-us/HT203977#computer
Hope this helps, stay safe!