I just switched recently from using insecure passwords to using KeePass. I was dreading the change, but it’s very easy.
I changed all my important passwords to highly secure, randomly generated ones and saved them to my KeePass database. That’s it. Took me like 30 minutes. Frankly I didn’t bother with accounts that don’t have any important info on them.
The upside and downside of KeePass is you have to keep track of your database file - it isn’t stored on the cloud, so unlikely to get hacked, but if you lose the file or your master password then it’s gone forever. If the cloud hosting isn’t an issue for you and you like that level of convenience, then maybe Bitwarden is a better choice.