You can share a magazine if the publisher has activated "Social Sharing" in the magazine settings.
Learn how to activate Sharing Links here
To find your magazines link go to "My Publications".
Then click on the cover of the magazine you want to share.
You will get the preview link to the magazine. You can either share that link or the direct link you receive by clicking on the "Read" button.
Sharing from the preview mode:
Sharing from the fullscreen mode:
Here is a guide on how to open a magazine on a s specific page