Is it possible for Steam to ask for pin when certain games are launched?

Hello guys, I have a problem. I just came home, and my temper finally reached its limit. My stupid-ass brother has literally no problem playing for 8 hours STRAIGHT every single day. He is the literal definition of failure. My guy has NO friends, NO bitches, and NOTHING in his head. I mean, he literally asked me whether (a + b)^2 = a^2 + b^2. Like come on, you’re already 17, dawg 😭

If he lived alone, he would just play games all day. His house would look like one of those before and after cleaning compilations on Instagram but without the after part.

And the WORST thing by far is that this little prick plays MY games. MY. And when I kindly request him to get the fuck away from the computer, he has the AUDACITY to start shouting slurs at me. LIKE WHO DOES BRO THINK HE IS 💀 He is literally nothing without me.

Now, finally, I said to myself, enough is enough. I’ll just disable access to my games, which is what he plays 90% of the time, since he’s a brokeass, jobless dumbass. I can’t just change my Steam password since he owns like 4 out of the 150 games I have there, and he has the right to play those.

But the biggest problem is that, from what I’ve read, setting up parental PINs on Steam is equivalent to learning quantum mechanics. Every single tutorial just doesn’t work, and every thread is old. I thought about making a simple program that would detect when my games are opened, but I don’t want to take any risks since games like GTA 5 have kernel anti-cheat, which can easily detect such programs and ban me.

So please, any help is appreciated. If the PINs no longer work, I’ll welcome other ideas. Also, you’d think that my brother is at least a little technically capable, but NO. He doesn’t even know how to send an email or print a Word document. That’s why I also have an app running in the background on my PC from which I can remotely shut it down through my phone if he angers me enough. Of course, that app can be easily disabled, but he doesn’t have the brain capacity to do that.

Thanks for the help.