First of all, you must be at least 16 years old to get your student pilot certificate. You'll need to be 17 in order to receive the regular pilot's license. There's no age limit for you to fly, as long as you qualify medically.You must be in great health. Everyone who wants to be a pilot needs to pass a medical exam in the early stages of the
process. Blind people with narcolepsy don't usually make good pilots. More on this topic later.

Finally, you must have an adequate grasp of the English language, being able to read, speak and understand it perfectly (English is the international language used by all airports and control towers in the world).

Commercial aircraft are those engaged in commerce. These can be anything from a Cessna C152 to an Airbus A380.

In all probability the number runs into several hundred aircraft a year world wide, but very few of these are major accidents, even at a C152 level of major accident. Certainly, very few involve serious damage to large passenger carrying aircraft.

The average might be two or three serious crashes in a year, but some years there are none, in other years several. Of course, there are differences between accidents and deliberate actions, which skew the statistics.