The only way to receive Fox network live programming for free is by receiving your local Fox channel via an over-the-air antenna connected to the antenna jack on your tv or other device equipped with a tv tuner.
If you can't do this you'll have to pay for it via part of your subscription fee to a service that carries your local Fox outlet, such as cable, satellite, or a streaming service with local stations.
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Ultra 4800 | Streaming Stick 4K+ 3821 | TCL Roku TV 43S245/C107X