Congrats on the new job!
I've worked at NMH in a few different nursing roles, both as a staff and contract RN across a few different specialties.
Orientation tends to vary quite a bit depending on what your experience level is and what unit you'll be working on and the amount of training required - for ex. ICU typically longer and intensive compared to med-surg, ambulatory.
Best advice, be eager and ready to learn but also make sure you communicate openly with your preceptor and educator throughout the orientation process. Always seek feedback, ask questions, check-in on progress every week or so, etc because it can be hard at first to gain trust amongst their staff.
As long as you you're a team player, hard working and willing to learn you'll do great :)
Northwestern also has tons of resources to supplement you're learning and professional development that you can seek out yourself if it's not more of a structured program with didactic classroom days/skills sessions. But if you're an experienced RN, it's really dependent on the unit and nursing culture how well orientation may or may not go so great.
Best of luck!