I was trying to use the obscure effect, and I noticed the guy on YouTube got a red square on his project monitor when he selected this. And I didn't get this red square, and this made it VERY cumbersome to use the obscure effect. And I noticed in the comments section on this video https://www.youtube.com/watch?v=tvB7LMWHYqg
that apparently I have to select "show all video effects" to be able to see this red square... and I have two questions...

1) Where is this "show all video effects" option?
2) WHY DO I HAVE TO HUNT THIS OPTION DOWN JUST TO HAVE FULL FUNCTIONALITY OF THIS EFFECT?!?!?!?!? I MEAN, DO YOU HAVE ANY IDEA HOW FRUSTRATING IT IS NOT BE ABLE TO SIMPLY MOVE THIS BOX ABOUT!?!?!? AND NOW I HAVE TO WONDER JUST HOW MUCH MORE DIFFICULTY I HAVE HAD OVER TIME SIMPLY BECAUSE I DIDN'T EVEN KNOW THIS OPTION EXISTED... I MEAN.... WHY!??! WHY!??!? WHY WOULD THEY DO THIS?!?!?!?

Okay... maybe that "show all video effects" wasn't the thing I needed (I never found it)... how do I get the red adjustable box to show up? Why do other people on older versions of kden I have red adjustable box? I don't have that box.

And how do you adjust the degree of obscure?

What version of Kdenlive are you using and on what platform (OS) ?

22.08.0

Linux Mint 20.3... I think

I think the box you are referring to is the edit handle frame. It can be displayed or hidden by enabling Edit Mode. Click the icon to the immediate right of the fast forward button in the project monitor.

And the "show all video effects" is the button that looks like a filmstrip right above the project bin. Effects are grouped by topic (video, audio, custom/templates, favorites), and by default kdenlive shows all effects (except the Custom ones for whatever reason). You can always search for effects by typing in the text field above the effects list.