To open the Task Manager on Windows 10, click in the Windows search box :
Type "task manager" in the search box
Click on the app :
The manager opens.
Click on the button to the left of More Details to open the full view :
The Process table shows you everything that is running on your computer. You will be able to identify which applications are active (in the background or not).
This table allows you to quickly see if your computer's capabilities are being overstretched and to terminate tasks that are using resources unnecessarily.
Identify the tasks you want to close, click on them and then click on End Task :