I am sort of in the same boat as you with learning and figuring out blueprints though I am inching closer to an intermediate level with my own experiences but it has been a struggle so that I can relate with you about.
To be honest, it really depends on what you want to do first then just knock out one at a time.
All of the above things you have mentioned can be found on youtube if you just look around there are UE4 Blueprint Tutorials for Switches, Buttons, Sliders, and such.
Here's some examples below that I found for you, just watch them and you can learn a lot even if it is somewhat unrelated.
Switch/Button to Open Door:
Slider Door but the same principles apply to it:
Also, if you are looking for more detailed help then it's best to tell what you have and haven't tried and provide some examples and screenshots to help so people aren't guessing at what you need help with exactly since the areas can be fairly broad.
Lastly, the best place to ask these kind of questions is at the Unreal Engine Answer Hub where you'll likely get a faster and more accurate response or even a related problem that is already answered similarly. You won't really find much help to something like this here. I would also highly recommend getting some tutorials from Udemy where you can learn a ton from others who are teaching. Some of them are free and a few cost money or are fairly expensive but if you wait and wishlist it a lot of them go on sale for about $10 and you can go pretty far there too.
Hope this helps push you in the right direction. I wish you the best of luck though and if you need more help i'll be around. :)