Thanks for reaching out. I'd like to inform you that users can share their Adobe Express projects via the share tab at the top right corner of the webapp.
Users need to click on Publish and then select the social media they want to share on, or they can click on Link if they want to share it on any other platform.
Please refer to the screenshots.
You may also refer to this article for more detailed info: https://helpx.adobe.com/in/express/using/share-projects.html
Let me know if it helps.