Tick anything you already have, in any order. Quests unlock once this is done.
Graded trails mean you can pick blue before red and know what you are riding into. Hire bikes on site are usually far better than what a beginner would buy.
Find a trail centre2 things left above. Quests are real things you go and do, so they only make sense once you have what you need.
First one waiting: Ride a rough descent standing, without gripping the bars white