Message # 1
can i upload game in my site?
Message # 2
You can upload files to another file servise and then place link on your site. It is most reality decision.
Message # 3
emon9184, there is an online games module you can install in the control panel.
This can be used for adding flash, browser and desktop games your users can play.
Install it by going to the inactive tab in CP, online games module, and install.