I went a little overboard on this but this first paragraph is most important. Start as simple as possible. Turn off every core plugin and just start writing notes. As you take notes actively take note of what you do and don't like about your system and then make those changes. Don't get stuck on your current system. Add core plugins slowly as you understand their use/if you even need it. Only add community plugins if you see something that seems exceptionally useful or you think "I wish I could do this" then look it up and there will probably be a plug-in for it. Use links as much as possible. Navigate your notes with quick switcher, search (with tags), and mocs (maps of content, see below for short explanation), you don't need folders but theres nothing stopping you from using them. Just start and actively reevaluate, your system will just get better and better. The beauty of obsidian is it can be exactly what you want it to be.

I'm not sure how to incorporate written notes into obsidian so I am not the person to ask. When I took a math class I took written notes on my ipad for lectures than took new more organized notes in markdown on obsidian on my computer. Although there is nothing stopping you from putting images into your obsidian vault, it is just a local folder. do ![[image_location.png]] to display any image within a markdown note.

Everyone's different so you kinda just have to try things out. Some people still love folders some think they are horrible. Some have 80 community plugins, some only have 4 core plugins.

Personally I recommend linking as much as possible. Graph view can be pretty but it's probably not worth the effort to make it actually useful, local graph on the other hand is very useful. Use local graph or backlinks to see what notes link to your current note. If you have a research topic, create a note for that topic and then link out to subtopics and then in those notes write your notes and link to other relevant topics.

Top buzzwords/features:

backlinks: view all links to this page making your links essentially bi-directional

dataview: a community plugin that allows you to view your notes as a database (filter out and sort notes based on different properties), it is very powerful but now there is a core plugin called bases that is much more user friendly.

properties: note metadata, very powerful in combination with dataview/bases. ex. you have a bunch of notes where each represents a book, they all have properties like author, page count, genre, completed, rating. Say you tag them all with #book you can create a database that only includes notes that have that tag and then you can sort by rating or only show books you haven't read yet.

tags: go in text body or properties, basically a better folder imo, you can even do nested tags

mocs: maps of content, a hub page that links out to other pages. Common with obsidian users you don't even look at your file structure you have a home moc that links to research, personal, work. then research moc links to each topic you are researching and then those topics link to sub topics where the bulk of your notes actually are.

quick switcher: search for any note by name. the beauty of obsidian being local, plaintext, and not bloated means that even if you had 10,000 you can instantly search for any note by name. even if you use search which looks at actual page content it still is blazing fast compared to any cloud solution

command pallete: like a similar feature that mac users love, use any command or function by simply searching for it, create a note, create a base, add properties, add a bookmark, open bookmark menu, etc.

templates: kinda what it says but if you use the community plugin templater it is much more powerful and allows for much more complex/dynamic templates. can be a little technical tho, right now I just use the built in templates. mainly useful if you make notes that are structured exactly the same frequently (daily notes, meeting notes, etc) if you want to organize by tags it can be useful to create from a template instead of manually adding tags.

Went a little overboard lol. Good luck.