>>14174881. Single speed chainring bolts. Be warned, the books can be a bitch to take off without a chainring bolt tool, but you can do it.
2. The chain might fall off unless you buy a narrow-wide chainring. Alternatively you can use a chain keeper like pic related... BUT as you can see it's basically a stationary front derailer, so just adjust your front so that it stays in the right spot and it should be fine