Why are am I here? Why am I alive, on this planet, at this time?
A big question? No, a deepity. In one reading, truth. In another, nonsense.
The word ‘why’ can be taken in two ways: why meaning for what purpose did x happen; and why meaning how did x happen. Let's look at ‘why am I here?’ from both perspectives.
In the first sense, the question can be rewritten as ‘for what purpose am I here?’. In the second, ‘how is it that I came to be here?’.