First of all, you need a phone plan that supports the necessary bandwidth. Even with that, there's usually a cap which going over costs a lot of money.
Wi-Fi is free from your own router so if you want to watch in your own house that's doable. It's also free from other places like Starbucks but wouldn't support video streaming from your own PC.
You'd also need to state what phone you have so we know what APPS are available.