A few questions

First do I have to do anything else to the files when I download them or do I just extracted them to the add-ons folder. (sometimes this doesn’t work)

And secondly how to I give a NPC a weapon they can use.

Thank you

If you are in the NPC spawn menu, you can select a gun on the down

Thanks , you know anything about the other question?

<steamfolder>/steamapps/<username>/garrysmod/garrysmod/addons
Is that what you mean?
You have to search a info.txt into your download, and then drop the folder with the info.txt in it into your addons folder as above here.