new to macros

Sub reorganize()
Dim a As Range, n As Long
Dim i As Long, j As Long
Set a = Range("A1").CurrentRegion
n = a.Rows.Count
For i = 2 To n
    If a(i, 2) <> "" Then
    For j = i + 1 To n
        If a(i, 2) = a(j, 2) Then
            a(i, 3) = a(i, 3) + a(j, 3)
            a(i, 4) = a(i, 4) + a(j, 4)
            a(j, 2).Resize(, 3).ClearContents
        End If
    Next j
    End If
Next i
a.Columns(2).SpecialCells(4).EntireRow.Delete
End Sub

Sub CompileUniqueEntries()
 
Dim Cell1   As Range
Dim a1      As Worksheet
Dim a2, a3  As Long
Dim b1, b2  As Long
Dim c1      As Long
Dim c2()    As Variant
Dim d1      As Boolean
 
Set a1 = ThisWorkbook.ActiveSheet
a2 = ActiveSheet.Range("A" & Rows.Count).End(xlUp).Row
 
For Each Cell1 In a1.Range("A1:A" & a2)
 
    For Each Cell2 In a1.Range("A1:A" & a2)
 
        If Cell2 = Cell1 Then
 
            b1 = b1 + Cell2.Offset(0, 2)
            b2 = b2 + Cell2.Offset(0, 3)
 
        End If
 
    Next
 
    If a3 = 0 Then
 
        a3 = 1
 
    Else
 
        a3 = (a1.Range("E" & Rows.Count).End(xlUp).Row) + 1
 
    End If
 
        c1 = c1 + 1
 
    ReDim Preserve c2(1 To c1)
 
        For Each element In c2()
 
            If Cell1 = element Then d1 = True
 
        Next
 
    If Not d1 Then
 
        c2(c1) = Cell1
 
        a1.Range("E" & a3) = c2(c1)
        a1.Range("F" & a3) = Cell1.Offset(0, 1)
        a1.Range("G" & a3) = b1
        a1.Range("H" & a3) = b2
 
    End If
 
    d1 = False
 
Next
 
a1.Range("A1:D" & a2).ClearContents
a1.Range("E1:H" & a3).Cut a1.Range("A1")
 
End Sub