Crossover (an alternative program running wine/proton) is a good recommendation and pretty much the only surefire way to have good performance and decent mod support. afaik parallels is also another way if you wanted the full windows architecture but I wouldn’t recommend it due to very unoptimised performance. Keep in mind crossover is a paid product and lifetime does cost anywhere from $60 to 90$ depending on where your located.

You can play Cities: Skylines 1 via Rosetta on your Mac so you don't have to do anything. Just install the game and play. Cities 2 can't be played. Even with Parallels it's a bad experience. Doesn't work in Crossover either. Otherwise Crossover is very good for playing other Windows games and it will go on huge sale on Black Friday or Cyber monday.