First, it's a pot second its in a tree not close to the river you have to shake the tree 3 or 4 times to get it out. Good Luck!
in a tree
mogul find on the sign on ski mountain
mogul
There's no key, you have to play the mission before it, which is case of the missing puffles.
JellyBean
Mogul
mogel
In the shelter.
in the cave
to find paper when you have a log on the fire put the survival book on it.
mogul
If you are talking about G's special mission the secret word is "mogul"