at least 2 years minumum experience, with ADAPT QUALIFICATIONS that allow you to tecah, once this is obtained, you are considered nearly a professional
Depending on where you live you can look for a location that teaches parkour actively, or you could possibly be self taught. If you possibly wish to teach you will need to learn professionally.
In the early 2000's
Master the arts of parkour, karate and gymnastics
I did parkour yesterday. I am doing parkour today. I will be doing parkour later on today.
The definition of parkour is individualistic, practitioners of parkour define parkour in their own way. However, all people can agree parkour is the freedom of movement.
David Belle is the founder of parkour, but no one 'made' parkour.
I'm sure it's been used before by certain people but never an official tactic
I would not rely on just watching parkour videos to learn parkour from. You have to be in tip-top shape to do parkour. You do not want to break anything.
Parkour can be start by run.
Invent is probably not the best word to use. David Belle developed parkour from age 17 but it's not as though Belle simply decided to call all the elements of the art parkour collectively. Around 1997 is when it started to become popular.
usually
there are no age limits in parkour