Update cell Values or Read Values in other sheet (change colour of autoshape with VBA code

HI,

I am new to Excel VBA programming and assigned to Excel VBA support project to work to increase the performance of excel with VBA programming.
I want to make an Autoshape change colour with value in side.
<80% Red
>=80% to 100%< yellow
>100% green
And the code I'm using is

Option Explicit

Private Sub Worksheet_Change(ByVal Target As Range)
  
      If Not Intersect(Target, Range("A2")) Is Nothing Then
          If IsNumeric(Target.Value) Then
            If Target.Value < 0.8 Then
                ActiveSheet.Shapes("test1").Fill.ForeColor.RGB = vbRed
            ElseIf Target.Value >= 0.8 And Target.Value < 1 Then
                ActiveSheet.Shapes("test1").Fill.ForeColor.RGB = vbYellow
            Else
                ActiveSheet.Shapes("test1").Fill.ForeColor.RGB = vbGreen
            End If
        End If
    End If
End Sub

The code works but one has to click in the cell value and press enter for the colour to change, this happens because the value of cell A2 is =Home!A2.
Can you help me to make the code work directly from Home!A2 or make this code work so that I don't have to click in the cell value and enter.