how to restore iphone 6 s

Which question does your "yes" apply to?

This one? By "restore", did you mean to reset/erase the phone back to factory default settings?

Or this one? Or, did you mean that are you trying to use a backup of the phone to restore or reload the data in the backup back to the phone?

Do not answer "yes" to both questions.

By "restore", did you mean to reset/erase the phone back to factory default settings?

Or, by "restore", or did you mean that are you trying to use a backup of the phone to restore or reload the data in the backup back to the phone?

In either case, you should plan to use either a Mac or PC. Do you have one available?