Yes.
When killed, they drop 0-2 leather and 1-3 raw beef. However, if they are killed by fire, they drop 1-3 steak instead.
They also give you milk if you right-click them while holding an empty bucket while they are alive. As well as this they will give you mushroom stew if you right click on them while holding an empty bowl while they are alive. And finally, they will drop five red mushrooms if you right click on them while holding shears while they are alive.
Yep, in a dark room place a mushroom on stone with the surrounding blocks being stone, leave it for a while, and it will spread.
Go outside and find them anywhere.
Left click the mouse while holding the mushrooms.
No
If you have 2 mushrooms and a bowl you can craft a mushroom stew.
Randomly around the map
The big mushrooms have not been added to the mobile version of Minecraft yet.
You can grow: Mushrooms Trees Sugar Cane Wheat
It was spread by minecraft creepers
yes under trees
do you mean mushrooms
You cannot 'cook' mushrooms as such in Minecraft. You can, however, craft a mushroom stew. You make a bowl with wooden planks in the same formation in which you would make a bucket, which turns out to be a bowl and you put that bowl in the lower area in your crafting GUI with 2 mushrooms anywhere else in the crafting grid.
To farm mushrooms, dig a room underground and plant the mushrooms in the stone. Wait a few ingame days and you will notice that more mushrooms have spawned around the ones you have planted.
If you are playing 0.5.0 or later, then make a small medium lighted room (bright enough so mobs dont spawn but dark enough to plant mushrooms). Mushrooms can grow on almost every surface so if your room is grass from an above ground house or stone from underground, then plant away and come back later. They will spread overtime and give you more to harvest.