"You can't open this application because this application not supported on this Mac"

I've been trying to install an emulator on my Mac for a few hours now, but every time I try this message pops up and I can't get past it. I already tried going into terminal, allowing downloads from unidentified developers, and rebooting it into safe mode, but I just can't get past it. I've tried with different emulators and watches a bunch of tutorials, but the same message and symbol appears. Please help, and thank you.