Ever think a file or folder, or even more is being accessed without your knowledge? This is a way to detect it.

 https://canarytokens.org/generate

This tool is incredibly useful for receiving email notifications whenever a file, folder, custom executable, cloned website, or any other item is accessed on your computer or PC. It functions exactly as advertised, sending an email notification promptly after the action takes place. This provides immediate alerts for any unauthorized access to your files. I trust that this tool will be beneficial for individuals who suspect that their PC is being used by unauthorized individuals.

https://www.makeuseof.com/number-scammer-how-to-check/

This article above is a very useful article that also outlines a few websites to reverse track phone numbers, mainly scam numbers that call you.  

     I have found www.spydialer.com, https://directory.youmail.com, https://www.phonevalidator.com/index.aspx, are other websites useful for reverse tracking scam phone numbers along with the best method is of course, BLOCK them! ;)

another good article is  

https://www.makeuseof.com/tag/how-to-block-scam-likely-calls/  it has a view videos to explain how big a business it is along with some great tips.