help me to correct my grammar mistakes please!thank you very much!

Doing exercises make life beautiful
Now a dayNowaday,more and more people enjoy doing exercises, (you need a conjunction like 'and' between 2 clause)I can see the old play Tai Ji and badminton in the part (what do you mean? where is the part? the park right?),the young go running,swimming and dancing in the sport centre,what makes the new lifestyle take place of the old so quickly？ (try to make several clause. I mean you need a 'period' between the clauses, not 'commas'. For example, do not combine the last question with its preceding clause.)
I think there are two reasons that people want to do exercises.In the one hand (you only say that after you say something opposite with the thing you will say here. I did not see any contradiction. 'Fist of all' or 'first' is better introduction word),doing exercises help us more health,as our life level is improving we start to know the importance of the health,the more money we get,the more fat we carry,overweight can cause a lot of illnesses.A set of research from E.L.L from US indicate that the healthy people live 3 years longer than overweight people,doing exercise can avoid to be over weight,so they want to be more health by it.
In the other hand,doing sports is a kind of fashion action for the young people which don’t want to be laughted at by their friends,they can meet new friend and connect with others while in gym, Studies show that people while in gym is 20% nicer and two times easier to get a girlfriend/boyfriend than any other social places.more and more people know it from TV and computer,that’s why the single and lonely boys and girls so crazy in doing sports.

In my opinion,what people want by doing exercises is keep theirself youngly and sociable!

I am sorry because I cannot check all your writing since I am in the middle of something else. So, I just have some comments.

in short, I think that you have your ideas but you still need to learn more about such funtamental grammar as sentence structure, punctuations, and trasitional words. As long as you can get the hang of these, you will see your writing improving.

Cheer!