Why does Ethernet appear on iPad in settings when blue tooth is turned on?

Do you have an USB Hub or other Adapter that includes an Ethernet port connected to your iPad? If so - and you don’t have an active WiFi network connection, you may see Ethernet settings within iPad settings.

Unless you have an Ethernet interface connected using a suitable hub/adapter, seeing Ethernet settings in iPad settings is indeed unusual.

While appearance of these settings is entirely benign and should not affect operation of your iPad, should you wish to do so, you might try a forced restart of your iPad:

Force restart iPad (models with Face ID or with Touch ID in the top button)

If your iPad doesn’t have the Home button, do the following:

1. Press and quickly release the volume button nearest to the top button.
2. Press and quickly release the volume button farthest from the top button.
3. Press and hold the top button.
4. When the Apple logo appears, release the top button.

Force restart iPad (models with the Home button)

Press and hold the top button and the Home button at the same time. When the Apple logo appears, release both buttons.