How to make a functioning door for people who do not know how to. DIFF 0.5/đźź©

How to make sliding doors (Difficulty::green_square:)
How to make doors that will open and shut (Difficulty: :green_square:)

I could only find two from the little “Link” area, but there are a ton of these. If you find something revolutionary, then this’ll get flagged as a duplicate.
Also the steps don’t hide, they say:

[details=“Step ?”] something

[/details]

Like on the outside of the details, not the inside.