I solved my previous problem connected to changing apache port to 8080, so that I could start nginx on 80-th port.

I set up a reversed proxy to create protected access to Kibana installed on server and available on localhost:5601

/etc/nginx/sites-available/default

    server {
        listen 80;

        server_name mysite.com;

        auth_basic "Restricted Access";
        auth_basic_user_file /etc/nginx/htpasswd.users;

        location / {
            proxy_pass http://localhost:5601;
            proxy_http_version 1.1;
            proxy_set_header Upgrade $http_upgrade;
            proxy_set_header Connection 'upgrade';
            proxy_set_header Host $host;
            proxy_cache_bypass $http_upgrade;
        }
    }

Now I have another problem. I restrict access to all of my site by 'server_name mysite.com;'.
mysite.com/kibana doesn't help me. What should I do?