Starting the exploration of Grasshopper bu using 3 simple lines. Once the confirmed design is wanted, hit the BAKE button will then confirm the design.
As the bake is done, the model cant be changed anymore. Drag it out and if want to do other iterations, hit points on of the curves. Then the curves can further alter it. The new shape after altering the points.
The yellow points are the points of the lines which can then be alter again.
As many curve can be added to form the loft. However if trying to loft open and close curves, nothing will be lofted as shown in the image below.`