In the task manager you just opened, go to Process and you can see which application is running how much RAM, and how much CPU. You can turn it off when you don’t need it.
Sometimes you can close it by right click> end task if your browser or excel hangs sometimes. Clicking on a hanger makes it hang more. Do not use more than 80% of CPU and RAM. If you continue to use 8090, it can be heavy. It is better to turn it off and use only what you need.