Hi guys. Own a MAC with Big Sur OS and was wondering from bad prior experience, whether I could run this if bought.

While I can't say for sure, as I don't have macOS and have no idea how I would go about telling if the current .pkg (were I to download it) is 64-bit, I do know that some time after the update was released that killed support for 32-bit applications on that OS, GOG removed mention of Mac support from the store page of any game whose macOS build hadn't been updated to 64-bit. The fact that Death Road's page currently lists macOS support along with Windows and Linux means that it's probably 64-bit, and will presumably work for you as long as you meet the other requirements.