Answer:
What object has keys that open no locks, space but no room, and you can enter but not go in?
Something you carry while singing.
I am always hungry, I must always be fed. The finger I lick will soon turn red.
It can be clear like water, but it burns like fire.
Every country has one, though we are not the same. Waving to our citizens, throughout the wind and rain. What is it?
What do you purposefully put lots of in and on your body, but run away from when you encounter it outside?