Excel VBA: find the union of two duplicate entries

I am new to vba and I've got two updating columns of text & I want to find the union of the two columns.

For Example:

... so on

I want to write the result in a new column A, B, C ... With column A

• number 1, 1 to 3
• number 2, 4 to 4 (if not duplicate at value column A)
• number 3, 5 to 5
• number 4, 6 to 7

like this :

... so on

How to work this out?

Please, use the next code. It will return in columns E:F, starting with the second row.

Sub extractMinMax()
  Dim sh As Worksheet, lastR As Long, arr, arrIt, arrFin, i As Long, j As Long, dict As New Scripting.Dictionary
  
  Set sh = ActiveSheet 'use here the necessary sheet
  lastR = sh.Range("A" & sh.rows.count).End(xlUp).row
  
  arr = sh.Range("A2:B" & lastR).Value2
  'place the range in a dictionay:
  For i = 1 To UBound(arr)
        If Not dict.Exists(arr(i, 1)) Then
            dict.Add arr(i, 1), Array(arr(i, 2))
        Else
            arrIt = dict(arr(i, 1))
            ReDim Preserve arrIt(UBound(arrIt) + 1)
            arrIt(UBound(arrIt)) = arr(i, 2)
            dict(arr(i, 1)) = arrIt
        End If
  Next i
  
  'process the dictionary content
  ReDim arrFin(1 To dict.count, 1 To 3)
  For i = 0 To dict.count - 1
     arrFin(i + 1, 1) = dict.Keys()(i)
      arrFin(i + 1, 2) = WorksheetFunction.min(dict.Items()(i))
      arrFin(i + 1, 3) = WorksheetFunction.Max(dict.Items()(i))
  Next i
  
  'drop the processed array content:
  sh.Range("E2").Resize(UBound(arrFin), UBound(arrFin, 2)).Value2 = arrFin
End Sub