Definition by WikiPedia
Email spoofing is the creation of email messages with a forged sender address. Because the core email protocols do not have any mechanism for authentication, it is common for spam and phishing emails to use such spoofing to mislead or even prank the recipient about the origin of the message. Source: https://en.wikipedia.org/wiki/Email_spoofing
How to Protect Yourself
Pay attention to the name and email address.
If they don’t match or make sense, you have a reason to be suspicious.
Look out for grammar and tone that seems off.
Grammar and tone are useful ways of identifying whether an email can be trusted. As email spoofers usually make use email addresses you are supposed to be familiar with or communicate with, they may not be aware of the tone usually used by the real owner of the email address
Contact the sender offline.
Don’t reply to a suspicious email claiming to be from someone you know if something raises the alarm. Call, SMS, WhatsApp, DM them and ask if they really sent the message.
Be wary of a request for action
Don’t click links or download file attachments you’re not expecting. Scammers use these as ways to get into computers or accounts. For business customers, do not provide any confidential information in reply to an email that seems suspicious