Since many of these lists come from infostealers, run a full antivirus scan on your computer to ensure no active malware is harvesting your new passwords.

If you reuse passwords across sites, change them immediately to unique, strong passphrases.

Even if the database contains old or duplicate data, it is used for "credential stuffing" attacks where hackers try the passwords on other services like banking or social media platforms. Immediate Security Steps

Adopt a manager to store unique passwords for every site, reducing the impact of a single leak.