Warcraft III is a game created by the company Blizzard. Players use the expansion game called Warcraft III: The Frozen Throne to play Gaias Retaliation.
In order to create a game, you first need to download the map located here. Then you need to place the map in C:\Program Files (x86)\Warcraft III\Maps\Download. If the Download folder is not there, then create one yourself. You should also make sure that you have the latest update for Warcraft III: The Frozen Throne by clicking on Battle.net.
Ways to Create a Game
There are several different ways to use Warcraft III to create a game of Gaias Retaliation.
The first is to go into the Local Area Network tab and click Create Game. Find the game in the Download folder and host it.
The second way is to go into Battle.net and create a game there. Battle.net is explained here.
The third way is to use a bot to host a game on Battle.net. Bots generally host on all servers on Battle.net and can be an autohost bot or a private bot. Information on bots hosting Gaias Retaliation can be found here. You can also use a public hosting bot to host the game.
Info regarding BGN
The last way is to use a program called Garena, which is explained here.