All information regarding running and developing S&Box on Linux will described here.
Steam > Library > Right Click S&Box > Click Properties
Compatibility > Click Force the use of a specific Steam Play compatibility tool > Select Proton Experimental
Proton Experimental works best, if this doesn't work try a different version.
At the time of writing (Jan 2022) you can launch s&box development executable but it is very bugy and is known to crash randomly.
Steam > Library > Right Click S&Box > Click Properties > General > Add
-tools to Launch Options