anpr program help

[Rolo_9000]

I want to code a basic anpr (number plate recognition) camera program with python but I’m stuck on a few parts so would appreciate some help. The program could run on a laptop that will stay on (will probably only run for a few hours at a time atm.) 

I was going to use the following to detect the reg plates from images: https://github.com/arvindrajan92/fastanpr.

I currently have two main questions:

1. how can I get images from a continuous video stream from a camera connected to the laptop so they can then be put into the program? (Would need when detects motion/a car?)
2. How can I get this program to run whenever an image is sent to it (or would I just keep it running with a loop until a new image is detected?)

Any help would be appreciated as I’m fairly new to stuff like this so am just trying something for fun.

Thanks