My brother was a great athlete at school and university. He played at the soccer team and showed good results .. until he got injured. He knows a lot about the inner life of football teams. Is it possible to somehow use this knowledge to get the money? Coaching or advisory work?

You could try coaching, but you will need a lot of practical and theoretical experience to be successful. For example, boxing theory can get pretty complicated, as you can see on combatsportevents.com/sambo-vs-krav-maga-what-are-the-differences/. A pretty complex topic to get into but they explain the basics well, so you should get up to speed. There are a lot of variables in every fight, of course, so you should find that blog interesting for learning all those factors. With a good fighting history and a solid knowledge foundation you can start your career as a boxing coach pretty successfully.

Now there is a great opportunity, using this knowledge, to make money! There are many soccer betting offers on the site https://100betz.com/soccer/, so knowing the rules of the game and predicting the outcome of the match, you can make the right bet and win!

It depends on what exactly sports. As for me sport is good hobby and you should use your skills and knowledge to play better. But for example if you are a fan of combat sports like for example jiu jitsu, you can use it for self defense. By the way I can share list of the best jiu jitsu gi, maybe you will choose some of them for you training.