Using Wifi (wireless) and connecting with an ethernet cable (wired) are two entirely different things. When your computer says something like "no connections available" it could mean your Wifi adapter is not "On", it's defective, or there are no Wifi connections available, When your computer is connected via an ethernet cable to an active connection to the internet, your ethernet adapter should be used to connect instead of your Wifi adapter.
If Wifi is your only option and it is not connecting today but it was working within say the last week, one of the easiest ways to solve the problem is to use Windows System Restore to roll Windows back to a point in time when your computer was functioning correctly. It allows you to undo system changes without affecting your personal files, such as e-mail, documents, or photos.
Video: Fixing a problem using System Restore
If that doesn't help, try restoring an earlier system image or backup.