Help creating a (left)sidebar

I’m trying to do the tribute page project (https://technical-documentation-page.freecodecamp.rocks/) as close as possible but I’m completely stuck in doing that nav-bar to the left. I already know how to do it in the top, and I did manage to make one stick to the left using “float: left” but I was told no one uses this anymore and I should stick to flexbox. and I tried. but I don’t know how to put the content, the text content, as in the link, to the other side, it just stays below the ‘white’ space as if there’s a content taking 100% of the width.

[https://media.discordapp.net/attachments/663401043995918350/993003016288477284/unknown.png]

I’ve lost the code but shouldn’t be hard to reproduce… I mean I always get the same result in the end. and I need help before I go crazy for what seems to be easy :confused:

ps: I also did work it out with position:fixed but I remember it started to mess my list, as if all

  • elements were merging together as soon as I tried to see if the page was responsive, so I decided to do not because I didn’t know how to fix.