what contract can you get starting as group

I am very curious to know about contracts, in the record business.
What are "the traps", sometimes "booby-traps",
How to protect you against scamming in the music business
What about the money you should get, more specific, you start a band with 4 fellow musicians, so 5 in total, 2 people claim and are responsable for writing most of the songs & lyrics to write songs, and they do. I suppose those guys, are paid more, because of their composing skills. This brings me to the question if there are chordians who had an experience with this topic, and what cut of the cake do they get. No manager money, just a group thing. I know that how bigger the name and fame the more the contract can be adapted, but I am not talking about the Stones, just about a regular group of musicians, who signed a contract, including booby-traps.
Example the drummer writes the lyrics, the singer the melody, and what will be their share compared to the share of the 3 other musicians.
I post this topic to help a few members here, who are proud to have "gigs", and who take this very serious, hoping to be famous (maybe to high) but at least getting popular.