When I want to type a special non-English character like Ø, on my Android phone I simply long press on “o” on the keyboard and it brings up every variation of the letter o you could think of.
On Windows, the best you get is “please memorise this giant list of four number codes”. If I’m going to have to google the code I’m probably just going to copy the letter and paste it into whatever I’m writing.
Why not add them to the damn emoji menu (Windows key + .)
If you have an Alt-graph key you can type more glyphs by hitting it while typing a key. Ctrl+Alt also acts as an alt graph key. Shift also changes the glyphs. On windows you need to switch to the English International keyboard for the alt-graph key to do anything if you are on the English US layout.
you can get this glyph by typing Alt-graph+L