How to limit the number of requests from one IP?

Question

htaccess

The site has an insignificant load, with a huge margin, but sometimes the site is instantly overloaded and requests come from one IP.
How can I limit the number of requests from one IP per second for example?
Is it possible to do this via .htaccess for example?

Will using Captcha solve the problem?
It looks like the issue is trying to download the site.

Answer 1

Is it possible to do this via .htaccess for example?

You can't
Use Fail2ban , for example.

Answer 2

Nginx Module ngx_http_limit_req_module
If you have virtual hosting with ISPmanager, in the www-domain settings