I’m new to this kind of switches, so

I think I will make use of this rotary encoder with switch:
https://www.addicore.com/rotary-encoder ... /ad267.htm
They have 5 Pins but how this work to get 20 positions is a question for me. I think this must be done in the software but how I don’t know.
I have looked in the Inputs section from FlowCode but I can’t find. Maybe I must buy an extra pack but this I don’t know.
How must I proceed and how does this work ?