It depends on the band. If you go to see some heavy metal band the concert will most likely have a mosh pit. If it is your first concert I would recommend not going in it but you can if you want. You will most likely get hurt in some way. Some concerts will have people on drugs and people who are drunk. Just try to avoid them. I would never leave a drink alone and them come back and drink it again and ALWAYS make sure to cover your drink with your hand. County band often have a lot of drunk people and rock concerts will probably have some type of drugs. Once the concert starts and you are in front of the barricade there will be no more rows so prepare to have tons of people pushing against you. You will probably get REALLY hot and sweaty and you might feel like you are going to pass out. You probably won't though don't worry too much. Behind the barricade is pretty chill nothing really happens there so that might be a good place to stay until you get more comfortable them move up more.