I'm an RN what's the best place to start to learn how to read basic images. I worked in critical care for many years and yes literally...

I would suggest picking a body part and a modality and just start scouring the web. It is ALL anatomy. X-rays are a great place to start since that is mainly what you will see. For examples, for chest X-rays:  https://www.radiologymasterclass.co.uk/tutorials/chest/chest_home_anatomy/chest_anatomy_start  or even https://www.youtube.com/watch?v=uo7ho8ZW2YY

https://radiopaedia.org/  is an amazing source but it might be a tough place to start.