Hi Dhananjay,
I am Sumit, an Independent Advisor and a 2-Year Windows Insider MVP here to help.
Usually, CMD doesn't run in the background unless some program states that so. As a first step, run Malwarebytes to find if it is malware.
Malwarebytes Cybersecurity for Windows, Mac, Android & iOS
Disclaimer:
This is a non-Microsoft website which would provide accurate and safe information. Watch out for ads on the site which are frequently classified as a PUP (Potentially Unwanted Products). There is no need to buy paid products to fix your computers as they do more harm than good sometimes.