Looking for an electronic device that best fits my needs. Do I need to use a kindle? iPad? Touchscreen laptop?

I am looking for a device that:

1) Its screen can be adjusted to a kindle like screen that can be used to read books and documents easily.

2) I can upload pdf files to that device and be able to read them.

3) It has a touch screen with an electronic pen that I can use to write on the screen and be able to save my writing in a pdf file.

What do you suggest? Any suggestion is appreciated.