If you create a home free of hazards and provide them with plenty of food and water, your curious, playful baby ducks will be able to waddle and swim on their own before you know it. Learn how to make ducklings feel at home, feed them what they like to eat, and keep them safe from harm.
Living things require energy to maintain internal organization (homeostasis) and to produce the other phenomena associated with life. Growth: maintenance of a higher rate of anabolism than catabolism. A growing organism increases in size in all of its parts, rather than simply accumulating matter.
Simple. The only organisms that survive are those that have the inherent instinct to reproduce. If an organism evolved that did NOT have the impetus to reproduce, it would have no offspring and thus it would become extinct. One way of looking at higher complex multicellular organisms like ourselves is that we were constructed (through evolution) by the cells that compose us as machines to insure their infinite reproduction.