Obsidian - Sharpen your thinking
Kinda big learning curve but worth it imo. You can link notes together and basically create your own personal Wikipedia/digital brain. I also use this as my journal. And all the notes are future-proof cause they're stored as plain text files. There's a very large extensions/plugins community too
Bitwarden Password manager
I use 1Password instead of this because it's a lot nicer and easier to use, but this is the next best thing as a free alternative