You can upload documents using the document manager.  In the editor for the home page or any custom page, there is an icon  this is for the document manager.  Position the cursor where you wish to insert your link to the uploaded document, then click the icon on the toolbar and you will be able to upload a document.  The upload feature is on the second of the two tabs displayed in the document manager.   When you have uploaded your document click the link to insert the link in to your page.