You can share a link to a published post. To do that:
Open your calendar section from the menu bar on the left.
Choose the accounts in the upper left corner.
Scheduled and published posts for previously chosen accounts will be displayed.
Choose the one that you would like to share a link to and click on the three dots button in the upper right corner of the post.
The drop-down list will be shown. Choose the Share Link button by clicking on it.
The link to the post will be copied to the clipboard, and you can use it by pasting it wherever you want.