Last week I worked 16 hours at this shitty fast food job. This week they keep sending me home early so I've only worked 3. Why are they doing this? The boss said he'd give me hours but now I'm gonna be fucking broke.

Can I make a RPG system just by combining all the rules I like from various different games I've played or read about or is that a recipe for disaster? My online friends want me to DM but I have no experience and can't decide on what to run lol.