I recently had about $40 of Play Store credit that was inaccessible to me for weeks. Google support just kept telling me “Okay, wait 24 hours and it should be good now.”

FINALLY someone got it straightened out, but during the course of it, I had to explain to support what Stadia was and why I didn’t have a gift card number.

First step is just installing one and using it. Let it save your accounts and current passwords as you use them.

As you add accounts, if you know you reuse the same password for some accounts, change those passwords to a randomly generated one with the manager.

As others have mentioned Bitwarden integrates really well on desktop and Android. Highly recommend it.