You could either use a Hyperlink in a cell so you click it and it opens your word document or you could look to use some VBA CODE to open Word up.
Use Alt + F11 then go to the Tools Menu and select References, then scroll down the list until you find Microsoft Word Object Library and click the box. Then use some code like this:
Sub OpenWord()
Dim wrdApp as Word Application
Set wrdApp = CreateObject("Word.Application")
With wrdApp
.documents.open "Add the path and file extension to open the document"
.visible=True
End With
End Sub