I can’t do the update. Even though it’s connected to the internet

Hello ~ Your screenshot shows you have Airplane Mode turned on so you are not connected to the internet. Turn it off and connect to WiFi…try again.

Use Airplane Mode on your iPhone, iPad, iPod touch, and ...

~Katana-San~

Hello again ~ Take a look here…

If you see No Service, Searching, or SOS on your iPhone or iPad - Apple Support

~Katana-San~

Hello ~ Looks like you are in Airplane mode…

~Katana-San~

Airplane mode is activated and there is no WiFi connection.

You will need to turn off the Airplane mode option, and connect to a WiFi network to complete the update.

Try plugging it in to a Mac or PC and doing the update through iTunes

Do you not have cellular service on your iPhone. Your most current screenshot suggests you don't cellular service, which you need as well.