Although the various ISP'S. like AT&T and Comcast have made it easier to hand out information about your wireless network there's no reason why you're forced to keep the information they set up originally.
First of all the information they give you is generally printed on a sticker on your router which means that should anyone get into your home they can just turn over the router and get the information to break into your network. Not a good idea. So you actually should change the name of your network and the password. To do that it generally involves logging into your device from a browser on your computer and then manually changing the settings. If you're uncomfortable doing that you can ask a more tech savvy friend, but it's a very simple thing to do using the information printed on the router itself.
So you have two things you actually need to change. You need to change the password to get into your router and then you need to change your wireless network name and password to something you can remember, and that a criminal who happened to break in your home or one to use your wireless network wouldn't happen to know. It's simple to do but it does require a few steps. You can always ask your wireless internet provider for information on how to do that as well.