In the Settings, you can choose to build freely or to copy examples. You can also choose the grid size of the build plate from 3x3 to 10x10 tiles.
Use the orange triangle as a landmark for the correct orientation of the example and the grid. The orientation of both can be adjusted. You can rotate both the build grid and the preview. You do this by grabbing and dragging it. You can also change the example to show the 'Top view' and the '3D view'.
On the bottom left side of the build grid, there are two buttons: a block with a +, and a block with a -. Use the + mode and click on the grid to add blocks, and use the - mode to delete blocks. Use the buttons on the right side (+ and -) to zoom in and out.