Explication code VBA

Sub Heure()

'Recherche de l'heure de lancement
    Worksheets("Planning").Activate
    Dim Reponse_2 As Variant
    Message = "Heure de lancement :"          'Définit le message                                            ' message.
    Title = "Heure de début "                                   'Définit le titre.
                                             'Affecte la machine systeme par default
    Reponse_2 = InputBox(Message, Title, Default)             'Recupere la valeur dans reponse
    
    If Reponse_2 <> "" Then                                 'Test si reponse est different de vide
    
    'Worksheets("Planning").Activate
    
     Cells.Find(What:=Reponse_2, After:=ActiveCell, LookIn:=xlFormulas, _
        LookAt:=xlPart, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
        MatchCase:=False, SearchFormat:=False).Activate
    
   ActiveCell.Offset(1, 0).Select
    Dim l_1 As Variant
        l_1 = (ActiveCell.Row)
        Dim c_1 As Variant
        c_1 = (ActiveCell.Column)
        
    If (c_1 + d) > 24 Then
    Range(Cells(l_1, c_1), Cells(l_1, 24)).Select
    Range(Cells(l_1, c_1), Cells(l_1, 24)).Interior.ColorIndex = 7
    
    Dim sup As Variant
    sup = (((c_1 + d) - 24) - 1)
    Worksheets("Planning").Select
    Range("F25").Select
    Cells.Find(What:=Reponse_1, After:=ActiveCell, LookIn:=xlFormulas, _
        LookAt:=xlPart, SearchOrder:=xlByColumns, SearchDirection:=xlNext, _
        MatchCase:=False, SearchFormat:=False).Activate
    ActiveCell.Select
    ActiveCell.Offset(1, 0).Select
    Dim j1 As String
    j1 = ActiveCell
    Worksheets("Planning").Activate
    Cells.Find(What:=j1, After:=ActiveCell, LookIn:=xlFormulas, _
        LookAt:=xlPart, SearchOrder:=xlByColumns, SearchDirection:=xlNext, _
        MatchCase:=False, SearchFormat:=False).Activate
    ActiveCell.Select
     Cells.Find(What:=1, After:=ActiveCell, LookIn:=xlFormulas, _
        LookAt:=xlPart, SearchOrder:=xlByRows, SearchDirection:=xlNext, _
        MatchCase:=False, SearchFormat:=False).Activate
    ActiveCell.Offset(1, 0).Select
    Dim l_2 As Variant
        l_2 = (ActiveCell.Row)
        Dim c_2 As Variant
        c_2 = (ActiveCell.Column)
    Range(Cells(l_2, c_2), Cells(l_2, c_2 + sup)).Select
    Range(Cells(l_2, c_2), Cells(l_2, c_2 + sup)).Interior.ColorIndex = 7
    Else
    Range(Cells(l_1, c_1), Cells(l_1, c_1 + d)).Select
    Range(Cells(l_1, c_1), Cells(l_1, c_1 + d)).Interior.ColorIndex = 7
    End If
        
End If
10

Planifier.Show

End Sub