If you need to attach any agreements, certificates or other documents to a shareholder page, search for the shareholder by name in Capshare.
At the bottom of their main page (as well as any certificate or grant page), you can drag/drop documents or use the upload modal in the right corner.
You can also upload documents to any Security or Equity Plan page. Simply navigate using the Dashboard to that page and upload. NOTE: documents on these pages will only be visible to users with view or edit access. See this page for the difference between permission levels.