If you do not know how to play Android:Netrunner yet, then your first stop is the official video tutorial by Fantasy Flight games. It’s very high quality and an excellent introduction into the rules
Once you’ve gotten the basics down, then before you jump into OCTGN, you should really take the time to watch the OCTGN use tutorial, to understand the basics of using the engine to play efficiently. This will make your first playthrough much more enjoyable.
The use tutorial is a bit obsolete by now, but the core mechanics have not changed a lot. You can also check this step-by-step guide by Tuism
Finally, we suggest you download and have the keyboard shortcuts sheet open while you play. While you can see the same things by right clicking on the tabletop, or a card, it might make things easier to find and get used to.