How do I link commandbuttons to combobox selection?

I'm hoping someone can help me figure out how to code some functions that are a little beyond my abilities. What I'm trying to do is b able to click command buttons and have Excel determine where to place letters on the workbook based on what is selected in the combobox.

So for example, if I choose 710300A, that SKU on the workbook is in cell C3. Start (S). Finished (F). Published (P).

So if I click 360 Start while the Product SKU has 710300A selected, an "S would appear in cell E3. If I clicked Reviews Finalized, an "F" would appear in cell I3.

If I changed the ProductSKU selection to 708287A, located in cell C14 on the worksheet and clicked 360 Start, Excel would know to place an "S" in cell E14.

I've attached the workbook I have so far, as well as an image reiterating this scenario.

Thank you for any help you can provide!!

Change the combobox properties:
BoundColumn=0
ColumnCount=1

Add the below to the very top of Module1

Public Product_SKU_Row  As Long
Public Enum Headers
    Spin = 3
    Video = 4
    In_Use = 5
    Photo = 6
    WebCollage = 7
    Reviews = 8
    Article = 9
End Enum

Modify the form's button codes as was done with Start360_Click

calculate the sku row in the worksheet:

Private Sub cboProductSKU_Change()
    Product_SKU_Row = cboProductSKU.Value + 2
End Sub

Private Sub Start360_Click()
    With Cells(Product_SKU_Row, Headers.Spin)
        .Value = IIf(.Value = "", "S", "")
    End With
End Sub

When choosing the column numbers for the cell, type Headers. then choose the header from the dropdown.