I've been using
https://keepassxc.org/ for years and years. I have it on my windows PC, Linux pc, de-googled android phone running GrapheneOs. Not on iOS anymore but had it on that too. It can generate passwords too, which I use this feature to random generate 15-20 long string of random numbers, letters in both cases and special caractors.
Excellent software, opensource so no secret codes in it.
I have my 'kee master file' locked into Syncthing,
https://syncthing.net/, so if I make a addition or update the password file on ANY device, everything gets auto updated on all devices immediately. You could use any cloud service for this like Nextcloud, but syncthing is like your own server, open source and super secure.
No matter what you use, your master password to open and decrypt the file needs to be stupid long, but something like phrase or phrases or saying you really like.