New ICU nurse here! Do you have any tips for managing the care of multiple critically ill patients simultaneously?

Yes, prioritize by acuity and walk faster.

Write things down, it’s easy to forget small things that make a difference. Organize your shift and have a routine, ask around how other nurses structure their day and pick out what you like the most. Make it your own!

but them on cpaps' ventilator machines for respiratory care

You should only have to manage 2 ICU patients at a time. Regardless, there's going to be times when both patients are unstable at the same time and both require your attention at the same time. The best advice i can give is to learn how to prioritize your patient needs and it's ok leave one patient room to attend to another patient if needed. (level 1 trauma nurse of 3 years). good luck and godspeed