@ModernVisage,
To be passionate in life, means you are passionate about everything you do. At 21 and with so much talent, no wonder you are in a state of confussion.
Willpower and motivation is part of being passionate, you strive to succeed and you are motivated to succeed, as you are passionate about the cause, direction.
The variety of talents you have have passion attached but your direction is what is the most passionate to you..
Comedy - to make people laugh, a passion to succeed in that.
EMT - a passion to save lives to make a difference
Martial Arts - a passion to be safe, defend yourself
Movie Directing - Artistic a passion to tell a story that others love
Bar Tender - A passion to communicate on everyones level
Music - artisic a passion to tell a story through song
Joining the Army - again a passion of saving lives and possibly a passion of seeing the world, travelling - flight attendant
Chef- a passion of food
Science / Physco therapy - a passion of knowledge /understanding and making a difference
I see some of the above as "hobbies", and people skills as well as income especially hospitality, in a part time position gives you income to continue to grow in other areas that you desire.
I see music, comedy, directing as (1) unit that all can be followed as a whole, yet individually throughout your life.
Physco and Medical is about helping people and I guess if this was me, I'd be deciding if that is what I wanted to do for the rest of my life as a living, seeing death and pain as well as good ,or if I could use this gift in another fashion and use my passions in song, writing. Which is an arduous long journey sometimes to succeed. But rewarding if it's your main passion.
Why not as I've tried to show, break it all down as to what could be used as hobbies, what is the core passion, value to you of all of it, therefore, what could be stepping stones and what could just be something you have achieved and no longer need, other than when it presents itself again in life.
Knowing nothing of the publishing world is only a matter of asking, reading, learning and finding. Writing itself flows, getting the finaly of the direction and expectations I'd suggest to take a writing course - to publication, I did one once, over the internet, life is about learning.