That is an EXCELLENT question. First off, it likely already has the necessary drivers installed. That said, it never hurts to see if there are updated ones available. Second, what make & model of a TV do you have? That will ultimately decide if it will even work for you.
***Note: This is only an educated guess. I will test this theory tonight after my wife returns home with my Bluetooth headphones. I will update my responce IF there is an issue. If I don't update, you can safely assume that it worked as expected.
Step #1 - With the TV off*, insert adapter into USB port on TV.
Step #2 - Turn on the TV and allow it a moment to install or recognize the new device.
Step #3 - Open the TV's menu. You may need to access either an input, settings, or setup menu. Look for the device. With any luck, you'll find it and an option to search for Bluetooth devices to connect to.
Step #4 - Make sure the headphones are in pairing mode. On the TV, start the search for devices, find your headphones, then select and connect! (Do this even if you have used the adapter and headphones together on something else, i.e. - your computer. The adapter is only facilitating the connection.)
If all goes well, they should pair and you should be ready to go.
[IF this does NOT work on the TV directly, but you have a cable, satellite, Android TV, NVidia Shield, etc. Check the box for USB ports. It MIGHT work that way.]
* - It isn't a problem for the TV to be already on. I just suggest this.