Internet is ruining the performance of the computer

[Mudbill]

Here's an image from my Task Manager. Just so you can see what to pay attention to, I marked some areas. Click the show all processes like Red said, then sort it by CPU usage. You can also see the usage down at the bottom. If you find something with a really high usage, check the process name and possibly description. That will at least give you a hint to what is causing it. It might be a good idea to google that process name; often that will give you information about this virus unless it's brand new.