I'm new to OSM and have some basic questions about editing

Hello everyone. I've just started the adventure of contributing to OSM and have questions. What is the etiquette when it comes to creating "areas"? As in, for example, a Walmart. Do you create an area around the entire property and level it as retail? And then the building. Do I call the building itself "Walmart" or do I just call it "shopping center" or whatever it's called and leave the Walmart part to a point? Basically what I'm asking is should buildings themselves be specific to the business or should that be left solely to the point?