First off, I admire you for questioning your situation, and realizing that you could be in over your head. You seem like a very conscientious nurse! Sounds like your facility has a very lax attitude about protecting the patients or the staff and facility. (Let me guess--$$$!)
I would suggest that, if you do want to stay there, you contact the Oncology Nursing Society (
www.ons.org) for core curriculum classes in your area. There are local chapters all over the US that have lectures and programs, and just joining ONS as a national member will get you lots of info. As I'm sure you are seeing, there is much more to oncology nursing than giving chemo, and without the experience and/or extensive training in the specialty, I doubt that you would have the know-how to handle what could happen in an oncological emergency, or to recognize some of the subtleties that could indicate a deteriorating disease state.
Or- "run the other way"-- to protect your license.
PM me if you'd like.