Changing Specific Cell Condition to a Range Condition - vba

Question

I would like to run a macro automatically when a cell changed(its value is equal or greater than "1") on G1:G500 Range.
I partially succeeded but;
It only works for one specific cell.
I could not write which tells it is equal or greater than 1. It only works if cell value is equal to 1.
I am truly sorry since I am a beginner at VBA. Helps appreciated.
Please see the whole code below;
Private Sub Worksheet_Change(ByVal Target As Range)
If Intersect(Target, Range("G12")) Is Nothing Then Exit Sub
If Target = "" Then Exit Sub
With Application
.EnableEvents = False
.ScreenUpdating = False
If UCase(Me.Range("G12").Value) = "1" Then
Call K999
End If
.ScreenUpdating = True
.EnableEvents = True
End With
End Sub

Answer 1

Try:
Private Sub Worksheet_Change(ByVal Target As Range)
If Not Intersect(Target, Range("G1:G500")) Is Nothing Then
If Target = "" Then Exit Sub
On Error GoTo GetOut
With Application
.EnableEvents = False
.ScreenUpdating = False
If Target.Value >= 1 Then
Call K999
End If
End With
End If
GetOut:
Application.ScreenUpdating = True
Application.EnableEvents = True
End Sub

Answer 2

Private Sub Worksheet_Change(ByVal Target As Range)
'[1]
If Intersect(Target, Range("G1:G500")) Is Nothing Then Exit Sub
If Target = "" Then Exit Sub
'[2]
If Not IsNumeric(Target.Value) Then Exit Sub
With Application
.EnableEvents = False
.ScreenUpdating = False
'[3]
If Target.Value >= 1 Then
Call K999
End If
.ScreenUpdating = True
.EnableEvents = True
End With
End Sub
Intersect(Target, Range("G12")) checks the target is G12 or not, according to your statement, it should be Range("G1:G500")
Since you cannot force the user type a number into the cell, it is safer to check the value is number or not first.
"1" is a string, 1 is a number. No need to transtype into string then compare two string.