How can an old (mature) man give life advice to a young man still in his high school days? First problem is finding the opportunity (what is called "quality time" nowadays) far from the distractions of modern life. Such occasions are rare. Then will he listen or reject the advice as just another harangue from a irrelevant grey-haired old codger. The time and place happened to me unexpectantly while on a walk in the bush - where better! Here is a synopsis of my impromptu talk.
Through a combination of luck and determination I enjoyed my working life. Working in the woods on the science of forestry was my bliss. "What you need to think about, John, for your future", I said, "are the five "Ms" - the five alternative paths of life ahead of you".
Your first option is to be a mercenary: These are the financially successful men who understand money and how to make it. Here you need to be smart, streetwise, believe in yourself and have determination, plus luck.
Your next and equally rewarding option is to be a missionary. Men whose work is their bliss and the monetary reward is a secondary. A commitment to study is often, but not always, a prerequisite for such a career. I guess I fell into this category.
Don't become a mug. These are the poor sods trapped in jobs they dislike or hate. Few will take the chance to find a better life. No difficulty to qualify here, just cruise along and take the easy path.
Even sadder is to end up a misfit. A weirdo, addict or worse who through misfortune or choice, lives on the fringe of society.
And I know you are not a potential mongrel. A thug or lawbreaker who passes his best years of life in and out of jail.
Look at your elders and peers in life and guess which "M" they are or will be. Then set your goals and choose where your heading.