To set up your Samsung Galaxy Note 4 to wireless display, you first need to go to Settings and under Connect and share, you will find Screen Mirroring. After you have selected Screen Mirroring, you should see [TV] and the Samsung Smart LED TV model that you want to connect to.
Once you have selected the Samsung Smart TV, you then need to use your TV's remote control to select Allow so that the connection can continue. You should immediately see the Note 4's screen on the TV.