How to check what rows are grouped.

[VBAMilennial]

My question is, how do I find which consecutive rows are grouped then store those rows and use them for other columns.

I'm trying to create a macro that allows me to take data from an excel sheet and place it in bookmarks of a word document. Below is the code I already have

Sub DocGenerator()
    Dim WordApp As Word.Application
    Dim WordDoc As Word.Document
    Dim r As Long
    Dim FileName As String
    
    Set WordApp = GetObject(, "Word.Application")
    FileName = ThisWorkbook.Path & "\Letter_"
    
    r = 2
    Do Until IsEmpty(Cells(r, 1))
        Set WordDoc = WordApp.Documents.Open(ThisWorkbook.Path & "\Letter_Word.docx")
        WordDoc.Bookmarks("CustomerName").Range.InsertAfter Cells(r, 1).Text
        WordDoc.Bookmarks("Data").Range.InsertAfter Cells(r, 2).Text
        WordDoc.SaveAs2 FileName & Cells(r, 1).Text
        WordDoc.Close
        
        r = r + 1
    Loop
End Sub

However, I'm drawing a blank where different customers have different numbers of parts and etc. The table below gives an example.

Customer	Data
Customer A	A1##
	A2##
	A3##
Customer B	B1##
Customer C	C1##
	C2##

<tbody>
</tbody>

Ex. How do I find that Customer A is grouped to rows 2 through 4, then take the data in column B - rows 2 through 4 - and apply it to the word doc?

Many Thanks!