Purple Black checkers board?

[thorn pier]

Means missing textures

[gusty crown]

yes, if you see this, you are most likely missing content for Half-Life 2 and its episodes, or Counter Strike: Source. both can be bought on steam for extremely cheap during sales! if neither fix it, you are most likely missing a required content addon.

in case you don’t know how to mount content, when you start gmod, look for the controller in the bottom right corner.