If you set it to its maximum size on the site (using the 'expand' icon in the top corner of the video) and then zoom into the window, you can get it full screen  it will be slightly pixelated, but it's better than watching it small, I've found.

You can stream BET for FREE online with a free trial of Philo. If you're out of free trials, you can sign up for Philo for as low asR$25.99/month, or opt to watch with DirecTV Stream (free trial). What is BET?