Nick wants to find out how to get started in learning how to code. It will take about a year to learn and become adept enough at coding to try and find work doing that. Nick already has certifications though, and he's in a good place to start. Leo says the worst case scenario is he'll just have fun doing it in his free time. Knowing how to code won't guarantee a huge success like with WhatsApp, and in fact the coding is the least of what they did. What made that app succeed is the design and user interface of it.
There are a number of sites that teach programming:
There's a book that was written by MIT and Duke University for beginning coders. Leo thinks this is the way to learn, and it's free to download. He can get it from htdp.org.