Try this:

Code:
Option Explicit

Sub NewDelete()
    Dim W1Startdate As Date
    W1Startdate = InputBox("Please Enter the Start Data in DD/MM/YYYY format")
    Dim lr As Long
    lr = Range("G" & Rows.Count).End(xlUp).Row
    Dim i As Long
    
    Application.ScreenUpdating = False
    For i = lr To 3 Step -1
    If Range("G" & i) >= W1Startdate Then
    Range("G" & i).EntireRow.Delete
    End If
    Next i
    
    Application.ScreenUpdating = True
    MsgBox "task complete"

End Sub

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