LEGO Mindstorms EV3 is the software required to create customizable, programmable LEGO robots.

From the main Window, you can jump right in with a quick start called "Getting Started." Once you're familiar with the app, you can find Software Overview, Content Editor, User Guides, and EV3 Help.

There are also numerous robots and robot remixes that you can download individually, and PDF documents that are easy to follow can be downloaded from the author's website. Getting Started is a video that walks you through creating your first robot and should be watched to become familiar with the app.