When adding a hyperlink, the user can paste in a copied link.
It is more involved if you want the link to be a file on a local network store.
One solution is to add a button to launch a file select dialog box to locate a file and return the full path and file name.
The current process requires you to
Copy the path from file explorer and add a backslash
locate the file, press F2 to edit, copy the file name and then paste that name to wherever the path name is
remember to add the file name extension.
This is one of those options that ex-Outlook users find challenging.