I want to be a soldier at the age of 20, but my parents and classmates disapprove of it, fearing that I won't find a job in the future. Is it not good to be a soldier now?

The worries of parents and classmates are justified. Being a soldier can really get a work curve, but it depends on whether you have access at home. Parents are worried that there is no way. Being a soldier can exercise people? That's true. But you are still young, and you have achieved nothing. What's the use of exercising again? My suggestion is to hurry up and learn some real skills. Joining the army rarely catches up with a good army, but it can also form a good style. Otherwise, you will learn nothing and leave a bad habit.