There is still so much to see and learn, so relax and enjoy . Your holiday is too precious to do a class. In a diving course you would be busy with lessons and exercises, so you would not see as much from nature. Float on the surface and forget all your worries. There is no depth gauge, no pressure gauge and no dive plan.
Rocky points are best.
Among the most interesting creatures are sessile organisms. Sessile organisms filter plankton, so they need current. Small animals need protection from predators, so they stay near plants and sessile animals. Fish hunt for small animals between plants and sessile animals. Don't try too hard to descend.