Okay,
Here is the deal. I do not want to sound rude or anything. Blowing out big clouds is a lot more than just hitting a button and inhaling. There is a lot that goes into it, and if it is not done correctly you could seriously injure yourself or others. Understanding Ohm's Law is the biggest thing. Battery safety and build safety. You need a few things before you just go buy a mod and rda and tell them to build you a set of coils.
Ohms meter, Legit 18650 (don't skimp on batteries.), The mod/dripper, tools, and wire.
You HAVE to understand safety before you blow big clouds. Sub-Ohm vaping is for experienced vapers.