Hl2 campaign episode 1 and 2 problems.

Hi guys, this is kinda hard to explain but, I’ll try!

Ok, I’ve borrowed a account with orangebox from a friend. He doesnt have garry’s mod, but I have it.
I managed to play hl2 campaign by extracting the “half-life 2 content.gcf” into the "steamusername/Garrysmod/ folder. Now when I played it through I wonder how to make it work for episode 1 and 2. I tried to extract everything that have “episode one and 2” in it’s name. When I enter in-game I can’t see any of the episode 1 and 2 maps there.

So… I wonder if anyone could explain how to do this with the episode 1 and 2.

Thanks in advance!

Isn’t that… illegal?

Just buy the game, less effort involved and you will be supporting Valve (which IMO is the best mainstream game developer)