Banks and corporations like Amazon, Microsoft, Apple and Geek Squad will rarely call you. If you do receive a text, phone call or email purporting to be from one of these organizations, it is almost certainly a scam. Hang up or ignore these messages. If you think a message might be legit, simply log into your account to check online balances and charges. If it appears to be from your bank, just call your local branch. 

Never let a stranger connect to your computer with remote software such as Teamviewer, Anydesk or Gotomypc. If you do, they will be able to access all of your personal data including passwords.

When using Google, be aware that the first results can often be scam sites that have paid to place their ads at the top.

Here's a great Youtube video that shows how the refund scam works.
"Turning the Tables on Scammers w. Jim Browning"

 And here's some advice on how to avoid being scammed from the USA Federal Trade Commission
https://consumer.ftc.gov/articles/how-avoid-scam