This may come off the wrong way (pompous/egotistical), but you don't go to high level approach facilities to learn to do air traffic. You go to high level approach facilities to perfect air traffic based on your own ability. If you're showing up here without knowing separation rules, an understanding of how to appropriately apply speed control, how to build gaps, how to hit gaps, how to hold gaps, how to work a frequency so there is little frequency congestion, etc. there isn't enough time or resources to teach you everything you need to know.