As a teen, its easy to not know what you are doing when you open your first bank account. Here are some errors to avoid. 

One common mistake some make is not checking the terms which is really important because some may have certain clauses which significantly change the account. 

Another issue is assuming the balance is always accurate, which might sound weird, but makes sense when you understand that money takes time to move so there are often delays in transactions, withdrawals, and more. 

Finally, another common mistake is that people disregard bank alerts, which are highly useful in keeping your account secured. 

By making sure you know about aspects of bank accounts like these are more, you are preparing yourself for success. I would recommend doing further research to ensure maximum knowledge and understanding.