How to block all net traffic except for X and Y?

Could someone please explain to me how to create a custom policy that temporarily blocks all network traffic except for the few software (video games) that I allow?

Thanks much!

Unfortunately, there’s no longer a way to temporarily turn off rules, a process has to be either allowed or blocked. There is the option to ‘ask’, but you would probably find that unsuitable. There’s also ‘Game Mode’…

Another option might, although it’s hardly convenient, be to have two different configurations. Perhaps, if you can provide some additional information, we might find a way to get a semblance of what you need.