I have keynote on my iPad, but dont use it to often. If I remember correctly it does show notes in presenter view, you can for sure add notes to it in Keynote on the iPad. You can import a powerpoint file, I just did a test with a pptx file and it worked. There will probably be some formatting things you will need to watch for once its in keynote, but it will go in fine.
“If you are neutral in situations of injustice, you have chosen the side of the oppressor. If an elephant has its foot on the tail of a mouse and you say that you are neutral, the mouse will not appreciate your neutrality.” Bishop Desmond Tutu