From the main Feed screen tap the Club icon on the bottom bar (green square).
Download your course: you can do this searching by Nearby courses, Countries or by tapping on the Search icon and writing the course name. After download your course once, it will be saved on the Synced list for future rounds, unless you delete the app. Then you'll need to download the courses again.
Now that you've already downloaded your course, you can play your round offline if you wish to.
Note: If you're a Premium customer and want to use the Notes feature, you'll have to play online. We're working to improve this for a future update.
On the Round Setup select what best suits your game. You can choose the starting tee by tapping on your name and on the starting tee. Make sure all the details are correct, go back to the Round Setup screen and Start.