Having a baby is a lot of responsibility, and it will not be easy. Of course, you are not expected to know-it-all before you truly experience being a parent. Still, as an adult you should be aware of how a baby can impact your life and if you are ready for all those changes.
A child needs your time, care, energy, sacrifices, financial support and whatnot. Make sure you are willing to do all that, so that you can honestly feel ready, happy and excited about the baby.