Why can’t I click certain thing on my phone?

The two basic troubleshooting steps are:

A forced restart of your device, using these instructions:--> Force restart iPhone – Apple Support

I avoid suggesting the second one, as you don't want to run it.

or,

you can make an appointment (*) and have your device inspected at an Apple Store or AASP (Apple Authorized Service Provider) among this list:--> Apple – Location Selector. After checking it out, they'll give you all the available options.

Regards

Giulio

(*) You can do it:

• Online:--> Genius Bar Reservation and Apple Support Options - Apple;
• Contacting a local Apple Store or AASP among the list provided above;
• Using the "Apple Store" app, available and downloadable from AppStore.