How do I type unicodes? (Kde Plasma)

ctrl+shift+u isn’t working for me, like it doesn’t do anything when I press it. And, when I started typing this, it said my topic was similar to another; I checked it out and discovered the compose key. Now that still doesn’t fix my problem. It appears the compose key has a very strange method of imput, like I had to type, “TH and th,” to get, “Þ and þ,”, but I can’t figure out how to type other letters, like yogh, that, and hiragana and katakana, which I used unicodes for all of them before, when I was using different dektop environments and window managers. I’d prefer keyboard solutions; I see in a couple forums people mentioning, “Just insert special characters in (whatever document writer program) then copy and paste elswhere.” That’s not what I want; it takes too long to scroll through huge lists of various special chracters, just to click on a couple to copy and paste them elsewhere.

EDIT: I fixed the hiragana and katakana issue by setting up fcitx, or whatever it’s called, to type japanese, so now I can type those letter like a normal human, but I still gotta figure out the other characters.

EDIT: I found the solution!!! Fcitx5 has the ability to insert special characters by pressing ctrl + alt + shift + u , but you have to know the name of the particular character, instead of typing in the code, but it still is a viable solution, that I’m happy with. Just follow the arch wiki page on Fcitx5: (was going to include the link here, but sadly I can’t; anyone reading this will have to look it up themselves…) (Might I add, that I restarted my computer after editing the /etc/environment file and adding Fcitx5 to my autostart applications list in the kde settings menu.)

Just search for manjaro-asian in package manager and install the one you need, I suggest fcitx5.