Welcome to CNC and the forum,

Word of caution first, these 3018 are very very basic and tend to be unreliable and not very accurate so if they don't produce parts you are happy with then don't dismiss CNC because it's most probably the machine (or user). Many many people produce fantastic stuff with CNC machines and your own imagination is often the limiting factor if the machine is capable, So I suggest if you don't get the results you expect then before giving up CNC you seek out experienced users with a better quality machine to see the difference.
I build CNC machines and see this often with customers who start or have experience with the cheap 3018 or WorkBee, Shepoko type machines, they are blown away with the difference between a properly built machine and what they were using, it really is night and day difference in most cases.

Good luck and don't forget to show the fruits of your labor as we all like nice pics.