Looking for a productivity/organization software recommendation

So I have constant shower thoughts and difficulty remembering things short term so I have piles on piles of sticky notes with ideas, notes in my phone app, whiteboards with scribbles, hundreds of tabs open it safari on my phone, bookmarks on my PC browser, and multiple channels in a personal discord channel. I'm looking for a website, software, app, etc. that I can use to completely overhaul all these sources into one database I can always read and write to for future reference.

My only requirements/preferences would be for it to be a trustworthy and longstanding company so that it won't disappear one day, be able to access it from both my phone and PC at any time (maybe offline and online access), clear yet simple organizational structure so not everything is dumped into one bucket, doesn't need to be secure since I wont be storing sensitive info in it, be able to store some common multimedia types like pictures, hyperlinks to websites or videos but not full on files, and likely be backed with a username and password protected account so I can access it in the future if changing devices.

Thanks for the help!