Answer:
I am one small little piece of paper yet sometimes hold lots of value. I am all you need to get in to big events but will cost you. I am an important part of travel. And if lost you're not coming.
No matter how much rain gets on me, I won't get any wetter. What am I?
Many people own a copy of me. Without me the world would fall.
I march before armies, a thousand salute me. My fall can bring victory, but no one would shoot me. What am I?
My first two letters say my name. My last letter asks a question. What I embrace I destroy.
The profession of Jimi Hendrix and Eric Clapton