Copying url link vs creating file share link

No, you are free to copy and use a URL for any of the pages throughout a DM in the same fashion.

If you copy and share the explore URL for a folder, anyone that tries to view that URL must have a TechDoc account and must have read access to that folder. If the user does not have read access, they will no be able to access the URL or view the contents of the folder.

When you say "open" the document, do you mean perform a Show Info on the document or a Fetch?

If fetch, you can either share links for individual documents (navigate to a document, click Show... Links on the side menu, copy and save the fetch link you need either latest gen or latest rev) or create a proper folder share (navigate to the folder, click Show... Shares on the side menu, then create a folder share). The users can then either access each of the individual fetch links for each of the individual documents or view the folder share and which will allow then to view all of the documents in the folder and click to fetch each of the documents. Again the user will have to have read access to each of the documents to see and fetch them.

If you simply need to share the Show Info URL for a document, just navigate to the document and either click Show... Info on the side menu and copy/save that URL or click Show... Links and copy/save the explore document link.