WordPress is a free and open-source content management system written in PHP and paired with a MySQL or MariaDB database. Features include a plugin architecture...
Update WordPress, your theme and plugins after taking a backup and checking compatibility. Remove unused plugins and themes, and only install components from trusted sources. Use unique passwords and enable two-factor authentication wherever available, including for your hosting and email accounts.
Give each user only the permissions they need, and remove access for anyone who no longer manages the website. Keep backups in a separate location and periodically check that you can restore them. If you notice unfamiliar accounts or suspicious changes, seek technical help. No single measure removes every risk.