First startup, scared sh*tless

Doing a startup with childhood friends is unwise. Especially if not all friends bring enough to the table. I'm assuming your friends don't have startup experience or other unique skills.

On the bright side you can probably afford to take the risk. If you fail it may take you a couple of years to get back on your feet, but you're young so that's OK.

I think you would do well to enlist the assistance of a mentor for your industry or at the very least hire someone who can help you and your team stay on task. Next, I would legitimize the business and create Bylaws, operating procedures, timeline and milestones checklist and go to market strategies. Then I would ensure everyone agree to abide by these documents. Also, make sure you include an escape clause for bad actors, that way you get rid of them early and inexpensively. (Hence Mark Zuckerberg vs Eduardo Saverin ). My final thought on the matter is this, have all your agreements and major decisions in writing, and signed and in-place while everyone is happy, friendly and on cordial speaking terms with one another. Therefore, when things do not go the way someone expects it to and this will become an issue eventually, you will a legal leg to stand on.

Dont be scared.
The worst case is you loose everything, and that would probably happen if you dont give up! Hope for that to happen!
After that u will be starting to drink a bit whiskey with ice. :) Take few days off!
ur girlfriend probably marries someone else!
Then, u passed the test! it's like trueman show! you are now inside the water, and you think u die!
Then you hit the wall! not wall street though :)
you look at the mirror you see u aint no Jim Carry. :)
Then, You will see the world differently. Another world! So awesome! never seen before! you will be born! u have no idea what i m talking about!
u will earn confidence like you are ronald trump, except you have $100 left, with maxed out credit cards.
bottom line "nothing happens"