You do not need an antenna to stream, but some people buy an over-the-air (OTA) antenna to enable viewing of local channels, like NBC, CBS, ABC, FOX, PBS, CW and primetime sports for free. It is okay to have both an antenna and a streaming device attached to your TV.
A couple of things to consider before buying an antenna: First, check your current TV bundles. A lot of packages include local broadcast stations and programming that might already suit your needs. Using an antenna could add 20-150 free channels, but the exact number of channels depends on your location. To find a listing of channels in your area, there are online tools where you can enter your location and view all the available channels that can be picked up via an antenna. Many streaming devices will offer some local content, but if you’re really thirsting for lots of local shows and sports, an antenna might be a good choice.
There are two types of antennas: indoor and outdoor. Indoor antennas are good for city and suburban dwellers and outdoor antennas are best for those who live far from a broadcast tower or in rural areas. There are hundreds of antennas to choose from, and you can install one yourself or find an installer to help, depending on your level of expertise.