Excel formatting

Hi Christian_Ecijan 

Adding a Power Query option (attached) for the record as VBA is probably (much) faster

let
    Source = Excel.CurrentWorkbook(){[Name="Table1"]}[Content],
    CustomDelim = ", ",
    AddedNextRefs = Table.AddColumn(Source, "NEXT_REFS", each
        if Text.Contains([Reference], CustomDelim)
        then Text.AfterDelimiter([Reference], CustomDelim)
        else null
    ),
    SplittedRefToRows = Table.ExpandListColumn(
        Table.TransformColumns(AddedNextRefs,
            {"Reference", Splitter.SplitTextByDelimiter(CustomDelim, QuoteStyle.Csv)}
        ),
        "Reference"
    ),
    AddedClusterIndex = Table.Group(SplittedRefToRows, {"Part Number"}, 
        {"DATA", each Table.AddIndexColumn(_, "IDX", 0, 1), type table}
    ),
    CombinedNestedTables = Table.Combine(AddedClusterIndex[DATA]),
    UpdatedQtyAndNextRefs = Table.ReplaceValue(CombinedNestedTables, each [IDX], null,
        (v,i,n)=> if i = 0 then v else null,
        {"Qty", "NEXT_REFS"}
    
    ),
    SplittedNextRefsToCols = Table.SplitColumn(UpdatedQtyAndNextRefs, "NEXT_REFS",
        Splitter.SplitTextByDelimiter(CustomDelim, QuoteStyle.Csv),
        List.Transform({2..List.Max(AddedNextRefs[Qty])}, each "Reference" & Text.From(_))
    ),
    RemovedIndex = Table.RemoveColumns(SplittedNextRefsToCols,{"IDX"}),
    RenamedRef = Table.RenameColumns(RemovedIndex, {{"Reference", "Reference1"}})
in
    RenamedRef

any question let me know

Christian_Ecijan 

Sub parts()

Dim i, j, k, m, n As Long

Range("F:XFD").Clear
k = Range("A" & Rows.Count).End(xlUp).Row
m = 2

For i = 2 To k
For j = 1 To Cells(i, 3).Value
Cells(m, 6).Value = Cells(i, 1).Value
Cells(m, 7).Value = Cells(i, 2).Value

If j = 1 Then
Cells(m, 8).Value = Cells(i, 3).Value
Else
End If

Cells(m, 9).Value = Left(Cells(i, 2).Value, 1) & j

If j = 1 And Cells(i, 3).Value > 1 Then
For n = 2 To Cells(i, 3).Value
Cells(m, n + 8).Value = Left(Cells(i, 2).Value, 1) & n
Next n

Else
End If

m = m + 1

Next j

Next i

End Sub

In the attached file you can run the macro for the intended distribution of the data. However with a quantity of 16000 the result would be returned in columns H:WQR for this part number.