Here is an example of what your desired macro code might look like:
Sub Try()
'Get the next row or column of data
Dim newData As Range
Set newData = curRange.Offset(1, 0) 'or curRange.Offset(0, 1) for a column
'Update the cells in the other tabs
Sheets("Tab2").Range("A1").Value = newData.Value
Sheets("Tab3").Range("B2:C4").Value = newData.Offset(0, 1).Resize(3, 2).Value
'etc. for each tab and range of cells to update
'Select the new data for the user
newData.Select
End Sub
Go to the Developer tab, click the "Insert" button, and then pick "Button" from the Form Controls section to attach the macro to a button. Then, choose your macro from the list by selecting "Assign Macro" with the right-click menu on the button. Once the macro is configured and linked to a button, all you need to do is change the data in the first tab once a month, click the button, and the other tabs will be updated automatically.