I don't work in Access, but the principles of opening a document and processing it from VBA are fairly universal and go something like the following code. One way to open at your heading would would be to set a named bookmark at the start of that location (say "bkHeading1") and then select that bookmark e.g.
Code:
Dim wdApp As Object
Dim wdDoc As Object
On Error Resume Next
Set wdApp = GetObject(, "Word.Application")
If Err Then
Set wdApp = CreateObject("Word.Application")
End If
On Error GoTo 0
Set wdDoc = wdApp.Documents.Open(Filename:="C:\Path\DocName.docx")
wdDoc.Range.bookmarks("bkHeading1").Select