All of the creative files you've built within the platform or uploaded into the platform will appear under the "My Creatives" tab on the left sidebar.
From here, you can organize your creative files by file name, file type, file size, or the team member who initially added the creative. Additionally, clicking on the three dots next to any creative file grants you the ability to view and edit your creative's details, clone the file to create a new ad, or modify your ad's click-through URL.
All of your creatives will be available to attach do your campaigns in Step 5 when you 'Launch a New Campaign' from the homepage in the new updated platform.