Can I sleep under a tarp rather than in a tent?
No, a fixed bottom of your tent is required.
Can I sleep in a hammock?
Yes, if your hammock includes a top and bottom that will keep you dry during heavy rain.
Is there a special route for beginners?
There is no such thing as a fixed route, only a fixed timeframe (in 2020 the time frame is 2 or 3,5 hours pr. day). You make your own decisions about how many controls to visit. You may choose to run or walk.