Method to filter based on dropdown list of months

Question

I'm trying to convert an Excel spreadsheet into Google Sheets. I have the entire year on a sheet and would like to filter the list based on a selected month from a dropdown. For example, selecting "June" would filter the page to only show June 1 through June 30.

Google Drive link: Google Sheets

OneDrive link: Excel Spreadsheet

I'm thinking I need to set the data validation of the dropdown to point to a secondary sheet and use a filter function to select dates with a position number corresponding to the month number (i.e. 1- January, 2-February, etc); but for some reason, my filter function returns an error message even if I attempt sorting by a manually entered date range ; (i.e.) date>=(2015,1,1), date<=(2015,1,31).

Edit: I just realized that OneDrive does not work with the VBA code. I'll attach it to this post:

Private Sub ComboBox1_Change() '2015 Sheet
Dim FromDate As Integer
Dim EndDate As Integer
Dim YearPortion As String
Dim NextYear As String

YearPortion1 = "-01-2015"
YearPortion2 = "-01-2015"

FromDate = ComboBox1.ListIndex + 1
EndDate = ComboBox1.ListIndex + 2
If EndDate = 13 Then YearPortion2 = "-01-2016"
If EndDate = 13 Then EndDate = 1
Sheet4.Cells(7, 1).CurrentRegion.Columns(1).AutoFilter 1, ">=" & Format(FromDate, "00") & YearPortion1, xlAnd, "<" & Format(EndDate, "00") & YearPortion2
End Sub

Answer 1

To convert YYYY, MM, DD to an actual Date object, you need the DATE command. The following works:

=filter(A6:F371,A6:A371>=DATE(2015,1,1),A6:A371<=DATE(2015,1,31))

But I see you want to filter based on dropdown entry. For this I would use MONTH function. For example, suppose cell J10 has validation rule: list of items

01 (January), 02 (February), 03 (March), and so on

Then your filter in J11 could be

=filter(A6:F371,MONTH(A6:A371)=VALUE(LEFT(J10,2)))

The idea here is that the names of month help the user in selection, but the filter uses the numeric format (month number).