Before trying to get into your router do the following:
- First, find out what model and brand it is, you should usually see this somewhere on the router.
- Second, make sure no one else within your house has changed the router settings, if they have, ask them about it, it IS possible to change the password.
- Lastly, find out what your gateway is, there are a few ways of doing this, but I usually just type "ipconfig /all" (without quotes) into the command prompt. (to open the command prompt, go Start > Run > and then type cmd and press enter or, press Ctrl + R then type cmd and press enter)
Once you have your router ip (or gateway) known, goto that ip in a browser, if it comes up with a password box, good job. There are a few lists showing the default password for routers
here is one [link], search for your router on it (if your router is not there, search google for another list or goto the manufacturers website and download the router manual) .
Next, when you are actually within the router page,
use this tutorial [link] , select your router, and game, follow the directions and you should be able to host.