Basic User list items , search, Edit from three sheets

..and for your second part of your question..use this.

Private Sub ListBox1_Click()
  
    If Me.ListBox1.ListIndex = -1 Then 'not selected
        MsgBox " No selection made"
    ElseIf Me.ListBox1.ListIndex >= 1 Then 'User has selected
        r = Me.ListBox1.ListIndex
        With Me
            .TextBox1.Value = ListBox1.List(r, 0)
            .TextBox2.Value = ListBox1.List(r, 1)
             
        End With
    End If
End Sub