maent to say me by the way not "you"
Yes
It depends on what you want to download, first get what you want to download off of garrysmod.org Maps go in the steam/steamapps/(username)/garrysmod/garrysmod/maps file addons go in the steam/steamapps/(username)/garrysmod/garrysmod/addons file
technically yes, there were a few updates it is still called Garrys mod 10 though
Buy Garry's mod 10 off of steam.
no because garrys mod requires that you have a game that uses the source engine
Steam
yes
You Do Not Get Garrys Mod Serials, You Buy it Off Of Steam Which can be found at steampowered.com its usually about 21 United States Dollars
E
no
You can buy it a garrys mod.com
You can't