What you should do?
Secure files containing confidential data with password
Double check sender of email asking you to click links
Never trust the sender if the email is sent from outside person
Do not spread spam emails to your contacts
Never mark the email Not Spam unless you fully trust
Share confidential data with trusted contacts only.
Do not share or store your password in plain text files
Keep your PC updated with the latest OS updates
How you can ensure email authenticity
Check if email is signed
If the email is sent by a legitimate sender you should see a signed by section in the details, if you do not see a signed by detail means that it might be a phishing email.
Email that is sent to you directly
Never Trust if you receive email having via information