Check out the current version of Wirecast from this affiliate link:

This video demonstrates how to connect multiple HD video Cameras to stream live video on the internet.

Create a 3 Camera studio that you can carry in your backpack.

See below for *Links to see the equipment demonstrated in this video below on Amazon (*Note they are affiliate links)
Most of the items can be found at:

-BlackMagic Design Mini Recorder
-Thunderbolt Cable
-Camera shown is no longer available a similar model is the Canon Vixia HF R70
or here’s a kit for the camera:
-BlackMagic Design Intensity Shuttle Thunderbolt
-BlackMagic Design Intensity Shuttle USB 3.0(note this doesn’t work on all computers–it needs a special chipset, contact the manufacturer to see if it will work for you).

***Connecting to the internet Via Ethernet is much better than WIFI, if you are using a Mac, I recommend using Apple’s USB to Ethernet. (Don’t try generic I made that mistake trying to save money and had to buy the right kind afterwards)

I have been asked many times for alternatives to thunderbolt adapters, I have not used the following, but they have been recommended to me many times
-This is a great PC option Magewell HDMI to USB 3.0

See how you can stream HD video live using an HDMI cable, Black Magic Design mini recorder and Black Magic Design intensity shuttle. The software demonstrated is Wirecast Pro 5. The software is available on Mac and PC