There is really only one part of your project that has any direct reference to Blynk, and that is the Video Widget.
However, first you need to Google for the various ways to stream video from an RPi using different types of programming languages and cameras.
Once you have the URL for the stream, you can then enter directly into the widget or possibly send it via Node-Red/Blynk integration… but again you probably need to learn that on Node-Red’s website, and by reading this link…