Migrating from one mobile platform to another is complicated and annoying. With Android Nougat, however,Google's making it easier to come on board from an iPhone.
That is, it's easier than before. Though it's still not terribly easy. Before, Google had a standalone guide that you could hunt down on your own. Now, when you first set up a new Android device on Nougat, you'll be asked if you want to bring your data from an iPhone or iPad. Then, Google will walk you through the steps.
Those steps are still long and complicated. If you want to bring over your contacts, you need to export your data from iCloud into a vCard file and import it into Gmail. Photos and music still require a big upload to Google's services. Still, if you're new to Android, this should help make things a little easier for you to figure out.