How do I restrict Chrome on a Mac

How do I prevent my child from using Chrome on my computer to bypass Apple Screentime content restrictions? Specifically to access adult content. And how do I prevent him from downloading Chrome when I remove it -- this is web based download not App store, so he doesn't need permission. It's fine to tell me to have a passcode on my computer but honestly I can't always remember to log out every time I get up from my computer which I use throughout the day and night. If it's set to go to lock screen after 5 seconds of inactivity then it's a terrible inconvenience to me all day long. Surely there has to be a way to simply block adult content via Chrome on a Mac computer. I can block it via Safari, but Chrome does not obey Apple controls. Restricting Chrome in the restricted apps section of Screentime does not solve the problem because he simply goes to Google and gets at Chrome there, or redownloads it from Google.