Step 1 :

Check Nginx web server/Proxy is already installed on your server

Step 2 :

Download and install Nginx Static Brotli module :

cd /etc/nginx/modules
wget http://dl1.centos-webpanel.com/files/nginx/modules/nginx-brotli-modules.zip
unzip nginx-brotli-modules.zip
rm -rf nginx-brotli-modules.zip 

Step 3 :

Now add nginx module configuration on "nginx.conf" :

nano /etc/nginx/nginx.conf

Now add this lines on top of the nginx.conf :

load_module "modules/ngx_http_brotli_filter_module.so";
load_module "modules/ngx_http_brotli_static_module.so";

Now add brotli compression configuration in nginx.conf file in http {section and before http closing }:

   #brotli
    brotli              on;
    brotli_comp_level   6;
    brotli_static       on;
    brotli_types        text/xml image/svg+xml application/x-font-ttf image/vnd.microsoft.icon application/x-font-opentype application/json font/eot application/vnd.ms-fontobject application/javascript font/otf application/xml application/xhtml+xml text/javascript  application/x-javascript text/plain application/x-font-truetype application/xml+rss image/x-icon font/opentype text/css image/x-win-bitmap;

Save the file and restart nginx :

service nginx restart
or
systemctl restart nginx

Go to one of the site to check :
https://www.giftofspeed.com/gzip-test/
https://www.websiteplanet.com/webtools/gzip-compression/

For advanced user you can check content-encoding via http header :

HTTP/2.0 200 OK
server: nginx
content-type: text/html; charset=UTF-8
vary: Accept-Encoding, Cookie
content-encoding: br