First thing you should learn is that iLogic is based on a computer code language called Visual Basic, it doesn't function exactly the same, but it's still recommended to learn it since it will help you set up all of the logic you need. Here's a YT playlist I've found to be very useful since it takes nice slow steps to teach every function:
https://www.youtube.com/watch?v=mM3zB3QWuv8&list=PLC601DEA22187BBF1&index=1
Keep in mind that iLogic doesn't allow you full functionality of a VBA application and doesn't allow you full access to the Inventor API, about 95% of it, pretty much all except Event functions and other advanced user interfacing is supported. On the other hand, iLogic gives you access to a set of iLogic snippets, which you see on the left side of the iLogic rule editor, these are basically like shortcuts to the most common parts of the Inventor API (Application Programming Interface).
I also recommend you go to the Inventor Customization forum for better and faster help with iLogic/VBA/API related posts and questions.