Sub Kalender()
Dim monat As Integer
Dim anzTage As Integer
Dim Jahr As Integer
Dim TagNr As Integer
Dim aktuellerTag As Date
Dim ws As Worksheet
Dim nxtRow As Long
Jahr = InputBox("Neues Jahr anlegen!", "", "2021")
If Jahr = Empty Then Exit Sub
nxtRow = 1
For monat = 1 To 12
Set ws = Worksheets.Add(After:=Worksheets(Worksheets.Count))
anzTage = Day(DateSerial(Jahr, (monat + 1) Mod 12, 0))
ws.Name = MonthName(monat, Jahr)
For TagNr = 1 To anzTage
aktuellerTag = DateSerial(Jahr, monat, TagNr)
If Weekday(aktuellerTag, vbMonday) < 6 Then
ws.Cells(nxtRow, 1).Value = aktuellerTag
nxtRow = nxtRow + 1
End If
Next TagNr
nxtRow = 1
Next monat
End Sub