I vaguely remember if I wanted to play it in single player, I would press select first before entering the code for it to trigger in the correct mode. LOL

⬆️⬆️⬇️⬇️⬅️➡️⬅️➡️🅱️🅰️🅱️🅰️Select Start

Gives you 30 extra lives in Contra on the NES

It’s not working? Try blowing into the cartridge again.

I previously used Nobara but recently switched to Bazzite. I think you can give either of these two a shot. I recall Nobara includes a one button install of nvidia drivers. Not too sure about Bazzite since I have an AMD gpu.

Both these distros are gaming focused. Only difference is Nobara is a traditional distro while Bazzite is atomic desktop based.