List Box Trouble Run Time Error

I am trying to move string from a list box when I have them Selected and a Check box is true; when these two are true the click of the command buttion should add them to the defined sheet. Please review my code and tell me what I am not defining?

Private Sub ADDBTN_Click()
     If ListBox1.List.Selection = True And CHBX = True Then
             Worksheets("CH") = UserForm1.ListBox1.List.Selection
             End If
              
End Sub

New to VBA and looking for any help to complete this

Thank you,