Hello, @kakha,
Actually, To protect your site, you have to enable restrictions from the server by contacting your service provider. You can try to use the security plugins as well there are lots of security plugins available you can use them at your own risk.
Further here are articles for a better reference to understand how to protect your WordPress site: https://www.wpbeginner.com/wordpress-security/ and https://www.wpbeginner.com/beginners-guide/vital-tips-and-tools-to-combat-comment-spam-in-wordpress/
I hope it helps.
Regards 8Themes Team.
