even if you know some tricks to survive, you should not forget to eat enough fat, because i have heard even if you have enough food and water you can die if you miss a spoon of fat in your body. so try to find nuts or insects.
sorry for my english, my first language is german.
In the mountains, due to sparse everything, one must reach lower ground or perish in the whistling winds. A forest will have abundant food for a hunter, but you have to eat meat and find water, difficult in pine forests. The jungle has great food but you must be very careful with diseases, insects and certain plants. Abandoned island, your doomed. On ice, well, get something warm, on sand, travel at NIGHT only, and keep an eye for signs of water
Water is the most important thing in any environment. If you find some, make sure it's not stagnant because it could make you very sick. If you can, distill it by boiling it and using some banana leaves or a clean sheet of metal to catch the steam and drip it into a container. In a tropical climate, insects and fruit should be abundant enough to provide all the nutrients you need.
Have you heard of the Life Straw? It was developed for poor, developing communities in Africa who can't get fresh water. It's a large, fat-ish plastic straw with iodine and carbon molecule filters in it. It makes any half-clear, dirty water drinkable.
It would be a very helpful thing to have, should the need for survival arise.
One thing you should do anywhere is always be looking for food and water. Because if it takes a few hours to find and prepare a 'meal' then you should search all the time. If you wait to look for food while you're hungry...it may be too late...
Yes Bear Grylls is the best at surviving. But use a mirror to get helicopter passing by or other things to see you. People can see the shin of a mirror from very for away.