My basic question is: What's the highest I can go with MacOS, without having to install the Sims 2 Super Collection?

Background info: I've come to the conclusion that my current Mac OS (10.8 Mountain Lion, if you can believe it!) is no longer sustainable in today's internet world. Until recently I was able to open emails on my Gmail account; that is no longer true. So... I need an OS that will allow me to access modern websites, but also support my current Photoshop version (which I absolutely cannot afford to upgrade). Seemingly I can notch up a few Macintosh levels and still have CS4 work, but how will that affect my Sims game? I'd really rather it be a seamless transition, where I wouldn't have to jump through a thousand hoops to keep all my CC working, but I realize this may not be possible. My current Sims 2 game was brought over from an even older laptop, via an external HD, so I didn't need to re-install anything, just make sure all the parts got to where they needed to be. Anyhow, that's my story.

Apple announced yesterday that they were discontinuing Rosetta in the upcoming MacOS 28, due out in fall of 2027. All apps built only for Intel chips will no longer work if you make that upgrade. Is CS4 an Intel only app, like the Sims 2 Super Collection, or a universal app? You are golden to upgrade as far as your hardware will allow, stopping at the current MacOS 26.4, to keep The Sims 2 working, and presumably also CS4. Go to the app in Finder, and right click, choose Get Info, and look near the top for what type of app it is.

Both programs say they're Applications (32-bit), which I assume is what I'm looking for. I don't know that I can upgrade all that far up the ladder though, without setting my machine on fire. I'm currently running OS 10.8.5, if you can believe it, and even THAT was an upgrade from what was originally on here. Well, you can see what my system specs look like in the first screenshot.