2 ways how globalisation affects a normal 14 year old boy?

Well, it very much depends on where said 14-year-old boy lives.

If he lives in China (which, statistically, would be the most likely), globalization might, eventually, provide a source of income. For example, he may get a job at a factory making iPhones and video game consoles (which is better than it sounds, since his other options might have been poverty). If he lives in the US, globalization affects him by giving him the ability to buy said iPhones and video game consoles.

The poorer the country he lives in, the more he depends upon globalization for access to medicine and healthcare; the US and Europe have had vaccines for a long time, but India only recently started getting them and still many places remain highly under-vaccinated.

In general globalization may also allow him to move to another country where his opportunities are better (though in practice immigration is one of the few areas were very strong international barriers---sometimes quite literal walls---remain in place).

In general it is probably beneficial to him, but not always, and often in quite different ways. In First World countries globalization gives us access to a wide variety of products from around the world at low prices; in Third World countries, globalization gives people access to jobs in factories and call centers that may not seem that great to us, but are often much better wages and working conditions than were available otherwise.

Globalization also has a number of cultural impacts, which may be particularly influential on teenagers trying to establish their own identity. An obvious example is anime, which I hear is still popular among teens (it certainly was when I was a teenager---wow, was that really over a decade ago?); anime is really neither American nor Japanese but a synthesis of the two, combining American animation techniques with the Japanese tradition of manga. It is thus a direct product of globalization. Similarly, American mass media is viewed in over a hundred countries thanks to globalization, and thus American books, magazines, films, and TV shows are popular and influential around the world. More recently "Bollywood" films from India have begun to achieve popularity in the US and Europe, making the cultural exchange more of a two-way street---and this would also have been impossible without globalization.