How to transfer data to new phone

More information.

Transfer content from an iPhone, iPad, or iPod touch to a new device.    

Set up your iPhone, iPad, or iPod touch - Apple Support

 Use iCloud to transfer data from your previous iOS device to your new iPhone, iPad, or iPod touch   

I'd advise you to set it up as new.

Have everything synced with iCloud, or have the original files on your Mac/PC.

Also make sure to copy files from specific apps saved in order to put them back on the new phone.

That done, simply set it up as new and start it all over. Yes, hard work, but the best for your new device performance.

If you want to skip the job, then do one of these:

Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

Use Quick Start to transfer data to a new iPhone, iPad, or iPod touch - Apple Support