Unfortunately, Lethal Company doesn't run natively on Apple Mac computers; there's no officially supported Mac download for the game. The game was not developed for Mac, and its developer, Zeekerss, has yet to create a Mac port for the game.
However, all hope is not lost if you want to play Lethal Company on your Apple computer. If you do want to run Lethal Company on Mac, there are some workarounds you can try, but they aren't guaranteed to run the game well - and some of them come at a cost.
How To Play Lethal Company On Mac
There are two ways to play Lethal Company on Mac, even though there's no way to play it natively. Those ways include porting and using cloud gaming. Unfortunately, as we mentioned, some of the ways to play Lethal Company do cost money - but you can always try to get it to work using free services, and use paid ones as a last resort.
You can either port Lethal Company over using CrossOver (paid service with a free trial) or Wine (free), both programs you can download from the internet. To do this, simply download the software and follow the instructions, as they differ depending on which you choose to download. Using Wine is best if you're looking to only play Lethal Company and no other games, since it has a relatively simple setup and you won't need to worry about paying anything or inputting your payment information.
In the way of cloud gaming platforms, options include airgpu and Shadow. However, almost all Mac cloud-gaming services cost money. You'll need to pay to access the cloud, which will let you play Lethal Company - and other games - just like you're on a Windows machine, on which the games natively run. This option is best if you plan on playing other Windows games on your Mac, since it costs significantly more than porting a few games over.