Click on the project's name or URL to view the prototype.
In the Pages tab of the sidebar, click the Get Links icon (second from the right) to get the link for that page, with or without the sidebar. Copy the link to share the prototype with others.
You will want a Shareable URL and links for pages without the sitemap that look like this:<http://######.axshare.com/pagename.html>.
More info is available from Axure: https://www.axure.com/support/reference/axure-share-basics