If you have difficulties to understand this, I really recommend to read the operation at Wikipedia: https://en.m.wikipedia.org/wiki/Voltage_multiplier
I remember I've studied this at school years ago and even though I knew how to build one I never really understood why it works. Now, years later, I read about the operation from Wikipedia and kinda got it, but not really, so I decided to copy the schematics here. It really was mind blowing to see the operation right from the beginning and in very slooooow speed! The simulation complements the theory so well that I got it immediately. I wish you'll have similar thoughts.
Have fun with the circuit and investigate deeper as you wish. For example watching the current flowing through capasitors might be useful.
I tried to make the example as clear and useful as possible, but I'd love to have feedback and suggestions to make it even better. Thanks!
