Where I can sell my game on this site

Online Game Distributors list thread. There will be other distributors but that comes down to researching more deeply.

Take a look at the big blue bar on the header of every page.

There is the marketplace if you are selling completed stuff. There are the classified if you are looking for help such as playtesting or workers, and there is Your Announcements if you just want to tell it to the world.

Remember that the site is designed around game developers, not around game players. It is a great place to sell game development tools, art packs, sounds, and other development-related stuff, but less ideal for completed games. There is some overlap and you might get some buyers, but this probably isn't the ideal place for a heavy marketing push for a completed game. There are many sites where gamers congregate searching for the latest apps and games.

Take a look at the big blue bar on the header of every page.

There is the marketplace if you are selling completed stuff. There are the classified if you are looking for help such as playtesting or workers, and there is Your Announcements if you just want to tell it to the world.

I couldnt see any game on the marketplace

You could just get a web page, and pay Google for some ads ...