The intersection is detected automatically and you can use it right away without creating additional objects. For example, you can snap to intersections by just moving a point close enough.
You can get even more for lines intersections. Just tap the intersection and select Create Intersection in the popover menu. A new point will be created at the intersection with all intersection angles displayed. Tap the point again to modify its properties or to remove it.
← How do I create an intersection of two lines or a line and a circle?