Can any one who tests game can test software?
One who test games, can they test software too? or they need any special requirements for software testing?
I'm going to start with my standard response: it depends.
I'm assuming you're talking about computer games and not board or other kinds of games, but the computer game industry has something of a reputation for using a lot of unskilled testers. That reputation comes from the fact that the large game development companies can call on gamers who think it would be cool to get their hands on the new hot game before anyone else (and some of them would do it free). That pool burns out fast but gets cycled quickly, too. Someone whose only games testing experience is from this group is going to be out of their depth in most commercial applications testing.
On the flip side, the skilled testers in the game industry would have no difficulty moving to commercial applications. They'd need to become familiar with the application domain but beyond that, there wouldn't be a problem.