quick advice, if you want to be secure with your own passwords:
1. use a password manager for ALL passwords. Make 'em long.
2. Use passphrases (4+ random words, e.g. Diceware style) for anything you absolutely MUST remember (e.g. password manager password, OS password...)
3. NEVER reuse passwords.
4. Turn on 2FA / 2SA on any site that supports it. Prefer TOTP instead of SMS.
5. Sign up for https://haveibeenpwned.com/