Use CrossOver. It gives you 2 week free trial. Also, do not download the game from itch.io. Instead, download the game from here: https://github.com/DlovanSl/ClassicUs/releases/tag/2026.5.27 for the latest version. Downloading from the itch.io site will give you an older version which will not allow you to make lobbies and find codes.
Download CrossOver: https://www.codeweavers.com/crossover?srsltid=AfmBOooWsfC3wtR8aVQKx-lhkdlAHbaq6M...