Get Familiar with Android Pie
Android Pie looks and feels a lot different than Android Oreo thanks to the major changes Samsung's made to its user interface.
Samsung's One UI (formerly known as Samsung Experience and TouchWiz) is on board Samsung's version of Android 9.0 and it'll take some getting used to.
This is why we recommend getting familiar with it before you move your device to the new operating system. If you're familiar with the software ahead of time you won't get caught off guard by the changes.
First, we recommend getting familiar with all of the changes from Google. To do that, take a look at our Android Pie vs. Android Oreo walkthrough. It highlights the main differences between the two operating systems.
You'll also want to get familiar with the the biggest changes Samsung's made to the operating system. To do that, take a look at our guide to the Galaxy Note 9 Android Pie update and Samsung's change log.