How to know malware and malicious software found if your computer

Hello, how are you?
Are you know your computer is malware and malicious software free.
Very simple to verification your computer. When a new software we found then we install it our computer. However , many software there is malware there may be luke. This software is very harmfull to our computer. To find the software you can first go run or press windows key+r.

Then type this diolog box mrt

Then you show a diolog box such it

and press enter or click ok

please show this screen shoot and make your work