It is impossible to remember 50 different complex passwords. Humans are bad at this.
The Solution: Use a Password Manager app like Bitwarden, LastPass, or Google Password Manager.
They generate strong random passwords for you and save them. You only need to remember one "Master Password".
2FA adds a second lock to your door. Even if a thief steals your key (password), they still can't get in without the second key.
This second key is usually a code sent to your phone via SMS or an app like Google Authenticator.
Recommendation: Turn on 2FA for your Email, Banking, and Social Media immediately.