It can be very difficult to detect a well-spoofed email message even when examining headers (but if you want to learn how, a web search should get you the information you want).

What I do, and strongly recommend to others, is two-fold: First, don't allow your mail reader to render HTML emails. Second, never follow any links in emails, nor trust that any other contact information is correct.

If you get an email from an entity you know, and it is asking you to follow a link or call a number, ignore contact methods/information in the email itself and contact the entity using your already established information instead.