there a lot of them .. some are free some you pay for ... I'll have a word with my buddy.. the dev and ask him which he uses. He is uber security conscious
his company may even offer one....i'll look
https://www.howtogeek.com/141500/why-you-should-use-a-password-manager-and-how-to-get-started/
this is a good article and is easy to understand .. you only need to remember 1 password for all your sites if you use one of these.
just had to change all my passwords.. someone tried to log into my accounts from a non google app, so Google blocked it an let me know.. seriously time to think about a good password manager.