Here's a brief overview below of one way to accomplish an NDI work flow to output your program feed from one computer to another.
On your Mac computer, you'll open PT and add in all your video and audio equipment like you would with a normal set up. Next, you'll need to select NDI as your source for "Program Output," which can be found in the preferences menu under the audio and video tab. On this computer, you could control the camera switching and video clips etc.
Now on the second Mac computer, open up PT and select the first Mac computer as your source for camera 1 (it should appear in the list as "MacBook Pro" or "Zach's MacBook Pro" or something along those lines). On this second computer, you'll be able to add in graphics etc and actually select and send out the stream. You will only "go live" on this computer.
*Having a hardwired network connection on both computers is recommended to prevent higher latency.
Now after you set this up, you should be able to find the first computer in the list of camera options on your second computer. See screenshot below.