Some military organizations have initial training broken into 2 parts. Basic training (where you learn the fundamental skills to be a generic soldier) and Advanced Individual training (where you learn specifics of your job field - like how to operate a hydraulic crane to load ammunition into a large truck). Infantry now has both of those schools combined. After these steps, you receive orders to report to your duty station somewhere in this wide world. There begins your career. Usually, you will start doing exactly what you were training to do in AIT. Have fun!