Read a verification code from a test message
A verification code is usually a short number or token sitting inside a longer message. The rest is branding, links, and legal lines. In a test, your job is to find the token and to notice if the message around it is wrong.
Read the plain text first
The message page on this site leads with the plain-text part. Codes are easier to see there than in a designed layout. Open the formatted view only when you need to check spacing, buttons, or structure. Remote images are not loaded, so a missing picture in that view does not always mean your email failed. The difference between the two parts is explained in plain text and HTML in the same message.
Compare the whole message
Check the sender, the subject, and the host inside any link. A test can look successful because a code arrived and still be wrong because the link points at a staging host you did not plan to ship. Read the digits, then read the sentence they sit in.
Give the message a moment
Mail is not instant. Leave the inbox page open so it can refresh, or reload it yourself. If nothing arrives, confirm that the form used the full address, that the sending service accepted the message, and that you opened the same name you submitted. A typo in the domain sends the mail somewhere else, and this site will never see it.
Keep live codes off this page
A code that unlocks a real account should not be delivered to a public inbox, even once, just to see the template. Use a private mailbox for that dress rehearsal. The reasons are in do not use a public inbox for passwords.