Advice for New RN

I accepted a position as an RN for 3 ICF homes. I have ten years experience working with the developmentally disabled as a direct care staff. I have worked as an on call RN and for the most part I feel familiar with the "system".

I am a new grad and after passing my boards continued to work in a direct care position/ RN on call position while going to school to finish my Bachelors in a year.

I begin my new job as a full time RN for the 3 ICF's shortly and am feeling anxious and would like recommendations on literature to read to feel more prepared for this position.

I have never worked in an ICF only IRAs. I have heard that the main difference between ICFs and IRAs is primarily billing.. is this an accurate statement?

Anyone out there have any suggestions or advice to give to a newer RN in this field?

Thank you so much