Mountains and Hills, to make one you will need terrain tools mostly the Raise/ Lower, Plateau and Smooth.
First Raise a ground by usng the Raise Tool and then use the Plateau tool on the raised grounds and it will look like a messed up box mountain or something like that. Most likely, it will have too much noised at the sides because it is in its Plateau state. Now, this is where Smooth tool comes in the job. Use the Smooth Tool and smoothen the sides that looks like noised and messed up and it will be smoothen and there, it will result in a mountain.
Test map below, though not might be a mountain...lol! For the hills, just same process, if you can imagine its image, you can easily apply it using the terrain tools namely Raise/Lower, Plateau and Smooth.