How can I remove trees or line up buildings that have been already placed?
Open your build menu. There will be two buttons that appear on your main screen. One is a dollar sign, $, and you tap/click that to sell buildings, including roads and decorations. The other button is a four-directional arrow, and you tap/click that to move buildings, again including roads. On mobile you can only move buildings into completely empty spaces. On browser/PC, you can displace other buildings, enabling you to rearrange multiple buildings. You can only move a building to a space occupied by one other building, however. If you can move it to a space with another building, there will be a blue color shown, if not, there will be a red/orange color shown. If the space you are trying to move it to is completely empty, a green color will show. When you move it to a space while a blue color is showing, you will automatically pick up the other building and will then have to find a place for it. Again, this displacing of other buildings is not available on mobile, only on browser/PC.