How do I entirely block an app with screen time on my Mac?

Hello all! I'm a parent who's extremely frustrated with Apple's screen time controls on our family's Mac.

I want to let my young kids have their own accounts to use the Mac for school and such, but I also want CONTROL over exactly what they can open and can't open.

I get that there's "time limits" to be set, but I want to COMPLETELY block certain apps. For example, Disk Utility, I don't want them to be able to open it for any reason.

I cannot find, for the life of me, ANY WAY to block a specific app on my kid's account. Am I missing something? I've googled, searched here, etc, and I can't figure this out. I assume there has to be a way to do this, but Apple's terribly designed cumbersome sprawling "parental interface" is such garbage that I can't figure it out.

Any help would be greatly appreciated.

Thank you.