Thank you for reaching out to the Constant Contact Community. It's my pleasure to assist you today.
I'm sorry for the confusion regarding the navigation when adding contacts. After you hit Continue, it should take you to a page where you can add the contacts to a list. Once you select the contacts and click Import, the contacts are then added to the account. Here is a great article walking you through the process of Importing from a file and one for Typing or Copy/Pasting the contacts in. Please feel free to reach out should you need anything else.
Thank you for choosing Constant Contact. Have a great day!