For Markdown, see Nick Milo’s great video on Markdown for beginners: https://www.youtube.com/watch?v=bBk2kg8Gm_U
He lists 6 things you need to remember. You can probably narrow down to ~4 (headings, bold/italic (pick one?), lists, links). Try it, you’ll see you’ll remember it after typing it 2-3 times.
There is no font or font size to change, no justification, no font spacing, no line spacing, no paragraph spacing, no floating paragraphs, no colors, no highlights and all the other stuff that makes documents look like unicorn vomit. So no, you can’t make your document look like you want. The formatting is restricted, it is done so on purpose (ok, not exactly true, there is CSS, but let’s not get into that if Markdown is already too much).
The question to ask yourself is which formatting option to “make it look the way I want” prevents you from taking notes? If you really want to take notes, then just do that. Many (myself included) will argue that formatting is a hindrance to taking notes, it impedes the flow of thoughts, not facilitates it. No formatting option will help with thinking…
Library and Information Science is a science, you get get PhD in that. For short and excellent summary, see
Zettelkasten, Evergreen, Atomic are huge topics, I mean it in a sense they are BIG idea, not necessarily COMPLEX ideas. A few people already summarized and gave specific tips. My primary school explanation is this: Take short, single-idea notes. Link a lot, avoid folders. That’s it.
But… Just like F=ma and E=mc2, primary student is perfectly capable of accepting it as a simple fact, and plug in the numbers, and get correct answer. But they will not understand the power, meaning, consequences of what they are doing. Is that what you want?
Many people linked to Andy Matuschak website. I highly recommend it, here is a link to the very top “head” note:
https://notes.andymatuschak.org/zhmLXArqiCMDr9Q13ViqN3hh3SmrKzjQxWAr
It can be overwhelming, but just read all main notes listed in the left panel from top to bottom. Do what he says and you’ll be the note-making master!
Good luck!