If you wish to join a team, you can do this on your registration page.
In your participant email, there is a link to view your participant details (please be aware this link does expire after 20 minutes but you can always request a new one via the expired link).
When viewing your participant summary, click the button to Join Team - as shown in the below image
If you cannot find your team, please contact email@example.com and we will be able to help you out.
If the option to join a team is not available this will be because the event is not taking team registration bookings.
More Information on Participant Summary page - Click Here