Wi-Fi won’t turn on.

That is usually a hardware failure. If Bluetooth is also broken it is definitely a hardware failure.

You can try a forced restart, and if that doesn’t fix it, back up and restore your device. If neither solves the problem it is time to consider replacing the phone (Apple can repair it for a fee, but that probably wouldn’t be a good investment)

Forced Restart:

• Press and quickly release VOLUME UP

     then

• Press and quickly release VOLUME DOWN

     then

• Hold the SIDE button until an Apple logo appears (15-30 seconds), ignoring "slide to power off" if it appears

The operative word here is QUICKLY; and try it a couple of times, the timing is a little tricky. If done correctly this will always work unless the phone has a hardware problem. 

Backup and Restore:

1. How to back up your iPhone, iPad, and iPod touch - Apple Support
2. Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

● If an app or feature on your device is not working, not appearing, or is restricted (grayed out), a frequent reason is it may have been disabled using Screen Time, or by an IT administrator if you are using a device owned by an employer or educational institution.

- Read this support article If your Apple ID or other options are greyed out in Settings —> If your Apple ID is greyed out in Settings - Apple Support

Tap Settings > Screen Time > Content & Privacy > scroll to Allow Changes and turn on.

- If the device is managed (Settings > General > VPN & Device Management), contact the IT department that is doing the managing.

● Situation where a VPN was preventing action —> Unable to sign out of my Apple ID on my i… - Apple Community

● Situation in which Terms And Conditions in Settings had not been agreed and was blocking access to certain features including automatic backups. —> My icloud and find my iphone are greyed o… - Apple Community