If you are considering joining the military, then you should be aware that you are going to have people in your world who are going to try to talk you out of it. They are going to tell you all sorts of things to try to get you to change your mind and many of these things will simply not be true.
An example of a time where someone may try to convince you not to join the military would be if you do not have perfect vision. They may tell you that you have to have perfect vision in order to join the armed forces, when in reality as long as your vision can be corrected with glasses you can join. There are certain jobs, such as pilots and snipers who must have perfect vision, but there are many other things that you can do.
People may also try to convince you that getting through basic training is nearly impossible. In reality, about 90% of recruits will successfully complete their basic training to be able to continue to pursue a military career. The training is tough and it does have a tough reputation, however, your success is what drill sergeants are mainly looking for.