How to setup end-to-end / client-side encryption, where do I find instructions?

Thanks, yes, I know this link and two things:

I don’t want server-side encryption, not at this stage, cos it’s a bit too complicated, too much risk for dataloss. And we are not connecting external storage (at the moment).

I am running this instance of NextCloud for a young political party and we mainly need to share documents and documents are mainly not personal, so, the need for encryption of personal files is minimal. But I’d like to give users the possibility to write personal notes that are not politically correct, or that are not thought through or whatever. So, yes, I’ve accepted the tradeoffs that encrypted files are not accessible from the web. I am thinking that a user’s tree could look like this:

    - ncUser
      |- something-I-share
      |  |-thoughts-on-marxism.txt
      | 
      |- my-encrypted-stuff
           |-spokespersons-latest-stupid-thoughts-according-to-me.txt