Opening a file with CommandButton without specifying full path

I have a main worksheet with a CommandButton that is meant to open a .xlt file which is in the same folder as the main worksheet. Rather than hard code the file path, I want to use something like:-

Private Sub CommandButton1_Click()
    
    Workbooks.Open Filename:="Blank form.xlt"

End Sub

I have also tried

Private Sub CommandButton1_Click()

    ThisWorkbook.Path Open "Blank form.xlt"
    
End Sub

Neither work! Where am I going wrong?

TIA