If the phone memory is getting full, first check for and remove things you no longer need:
Instead of removing them, you can also move the files to the memory card.
The quality of your memory card may greatly affect the performance of your phone. To get the best out of your phone, use a fast 4‑128 GB card from a well-known manufacturer.
Use only compatible memory cards approved for use with this device. Incompatible cards may damage the card and the device and corrupt data stored on the card.
You can’t delete some apps that were pre-installed on your device. But you can disable them and they will be hidden from the list of apps on your device. If you disable an app, you can add it back to your device.
If an installed app depends on a removed app, the installed app may stop working. For details, see the user documentation of the installed app.
You can add a disabled app back onto the list of apps.
You can copy photos, videos, and other content created by you between your phone and computer to show or store them.
Make sure you put the files in the right folders on your phone or you may not be able to see them.