Does the game contain Linux installer as a "goodie" or it's like the game page says that we've got only Windows installer here? It's a bit strange. The game has been released for all platforms and is available for Linux natively elsewhere...
The LSL Reloaded title offered on GOG is supported on Windows only as shown on the game's page: https://www.gog.com/game/leisure_suit_larry_reloaded
Game executables would not be in the goodies section, as that would not make much sense.
Referring to other games with multiple OS support (excepting games like LSL Reloaded as the following cannot apply), then from any system on any web browser, you just go to your library, click "⋁
", then "More Downloads
", and the upper right part of that window has "System:
" which is a self-explanatory switch for changing the installer(s) to use for that system. Usually the installer(s) displayed at default correspond with the system you're using so you wouldn't need to switch systems.
So, obviously if you don't have that option to switch systems, then the title is not supported on other systems, so there will be no such installer for it.
For LSL Reloaded specifically, the only Linux (and Mac) support is only available through Steam, but it can no longer be purchased directly through Steam unless you get a Steam key elsewhere.