@variablepulserate currently I use Bitwarden on my desktop and mobile browsers. Open Source and free but you can also pay $10/year for a couple extra features, which I do.
There are a couple schools of thought on them: use something completely offline (which is inconvenient but more secure) or use something that syncs everywhere and can integrate into your browsers, which can be a security risk. It's a tradeoff.
Make sure your master password is long and strong. Also you may have to keep a handful of passwords "knowable" (such as your master password). For "throwaway" sites definitely use random, strong passwords.