>>2757722Depending on how chronically online you are, start doing physical exercises, running for an example.
Picking a random nearby hiking route or just a train in the woods should be safe enough (be sure to check).
Use google maps to vaguely check the distance and elevation (expect about 3-4km/h (2-3 miles) for non concrete roads and avoid more than 5-6h of hiking for your first trip) and take an early morning bus or something to there, then just set off. You should be fine for literally any conditions for a 6h hike, no matter your physical condition.
Pack up some snacks and depending on temperature, between 3 to 6l of water for an prolonged hike.
And that's about it.
PS if you're a fat fuck, buy some synthetic underwear, it doesn't chafe.