I’m pretty new to CoRE myself. For some answers you can look at my walk thru for setting up your first piston.
For some of the motion sensor stuff you need to also think about the hardware you have. Most (if not all) motion sensors will have a built in “blind time” where they don’t change their status (either motion or no motion) regardless of what the actual sensor shows. So you need to determine what your built in time is on that (and some devices allow you to change it).
But you can within CoRE also use delay times so coupled with the built in delay you should be able to achieve what you want.
Also do check out the wiki because it does explain the basics. You may want to (I typically like doing this because it really helps me) to write down your piston in logic terms (IF, THEN, WHEN, etc.) on paper just so you know the flow of the logic you’re trying to accomplish. That should help with realizing when one condition may interfere with another.