This assumes that the code will be run from module1 of the workbook that you are creating.
It also assumes that your template is saved as a .xlt or .xltx file.
Dim wb As Workbook, sh As Worksheet, wb2 As Workbook
Set wb = ThisWorkbook 'Your master workbook
Set wb2 = Workbooks(the name of your Template workbook here.xltx?) Your template
'Use an input box to determine the month for sheets to be produced.
mo = InputBox("Enter as a numeric character month number that you are adding", "MONTH NUMBER
'Get the number of days in the month assigned to a variable, using Select Case
Select Case mo
Case Is 1, 3, 5, 7, 8, 10, 12
ld = 31
Case Is 2
ld = 29 'This will cover Leap Year and 29th can be disregarded if not needed.
Case Is 4, 6, 9, 11
ld = 30
For i = 1 To ld 'Run loop to generate and name pages from template.
Set sh = wb2.Sheets1.Copy After:=wb.Sheets(wb.Sheets.Count) 'Add to Master workbook.
sh.Name = i & " " & Format(ld, "mmm")