HELP - Dual Booting

I do vanlife and got the deck specifically to be able to game with my friends while out traveling. We want to play Black Ops 6 together and due to Linux not being supported, I’ve dove down the rabbit hole to dual boot the deck.

I’ve successfully installed windows 10 on a micro SD and have it running on the deck. However I just used a spare card that’s only 64 gb. BO6 is 100gb alone.

Is my best bet to just accept defeat and start over with a larger card and download windows and the game to that? I already have the game on my internal 1tb drive.

I am completely new to the PC world and even the YT tutorials are confusing as hell and everyone in here speaks another language it seems.

The deck is proving to be significantly more complicated to use than I had hoped.