I’m trying to make the base terrain that my entire low-poly city map is gonna sit on. Although I’m not sure how to make the terrain, I just want the grass and such as I’ll put the other stuff on it. Should I just color the baseplate or should I try and make hills in blender and put that big plane as the terrain? I really need help as I’m very clueless 
There is this one plugin which helps you to make them. Now you needs few things like a auto generated map, the paint plugin which helps you paint a part, a very small part (1,1,1 maybe?) and this plugin. I will link you a video which explains how and the plugins required will be supplied over there.
