1099 NEC and Schedule C

I did side job in landscaping, so I understand why I am getting a 1099 NEC from the owner .  Its prompting me to then fill out a Schedule C, but its is asking "in depth" questions that I have no knowledge of.   For example:  

Accounting Method, Method to value closing inventory,  Material participated(?),  All investments AT RISK, Simplified Calculation of Amount of Risk.    This is confusing for the minimal of $2800 I earned .   Any guidance is appreciated.     I haven't spent a dime, not my business, just my labor.   Thanks