why apps are disabled

Don’t worry, it will turn out alright. Push comes to shove, you can call Apple support and have them work with you. Without adequate information, I’m afraid I won’t be able to provide a good enough answer. Once you explain the situation to Apple support, they will be able to provide you with a solution.

You can always try resetting your phone, just hold down the power button and slide the power slider to the right. To turn it back on, hold the power button again. If it is an iPhone X or later, hold both the power button and upper volume button.

It might be the screen time settings, but without any further information I can't be sure. How exactly are they blocked? Do they not even boot up? Are they grayed out? Do they not appar, or does the app logo seem distorted or different? Which apps are being blocked?

What are you trying to do and what is the EXACT message you're getting?

Like what KiltedTim said, what is the EXACT message you are receiving? And is the settings app also disabled?