When registering for an event, there is a "Team Information" page that you will complete. This is where you will select which age group you want your team to play in for the event and will be the Team's "Event Age".
You can also choose to select playing up a year. For example, if you are U13 and want to play U14, this is where you will choose that option. Simply, click on the "Event Age" dropdown and all ages will appear.
Further, this would be the page/step within the event registration where you would be able to select the Preferred Division if made available by the event, select a Roster Source if enabled by the event, and where you can enter your GotSoccer Team ID number if not already associated with the team