Corrections in red.  Stylistics in blue.

Can you check my homework? Thanks =)

Today I want to talk about lifestyles. Unfortunately, many young people prefer to drink alcohol and smoke cigarettes than practice sports. I guess people don't understand that this affects the future of their children. If you smoke, you are providing a bad example. Find a way to drop this negative habit. If you want to be healthy, then choose the right way. Because only foolish people smoke. If you are smart, you will find something worthwhile to do. You can play football or chess, or listen to music -- whatever what you like. Your friends may even offer you their support!  Some people have been drinkers for many years. Maybe it's time to stop? The power is in your hands! You can do it! Don't pretend that you can't do it. I believe in you!

Thank you to everybody who helps me! Maybe can you can advise me how to better learn English?