Your goal is to deliver resources into the central terminal. Each level has a different requirement for which resource you need to deliver.

To deliver a resource, you must first place an extractor over the tile in the map. Select the extractor by clicking it in the bottom row, then click on the resource tile in the map. Next, click the conveyor belt in the bottom row, and drag in the map to create a path from the extractor into the central terminal. Always look at the direction that your buildings are facing before you place them! You can rotate whatever building you have selected by pressing R.

Click on any open space in the map and drag, or use WASD to navigate your view around. You can also zoom in and out by using the scroll-wheel on your mouse. 

In later levels, you'll get access to new tiles and resources. If you are ever stuck about how to proceed press the 'Hint' button in the lower left corner. Build up your factory and deliver lots of resources to unlock new upgrades!