Enable HTTP/2 in Apache Web Server on Ubuntu 22.04

sudo apt-get install php8.1-fpm
sudo a2dismod php8.1
sudo a2enconf php8.1-fpm
sudo a2enmod proxy_fcgi
sudo a2dismod mpm_prefork
sudo a2enmod mpm_event
sudo a2enmod ssl
sudo a2enmod http2
sudo systemctl restart apache2

After enabling and loading necessary Apache modules, navigate to your Apache configuration directory and edit Apache configuration.

To enable HTTP/2 on your Apache web server add one of the following to your global Apache configuration or inside of a particular virtual host.

Protocols h2 http/1.1

Here is the minimal virtual server configuration that can be used to enable HTTP/2 in some virtual host:

<VirtualHost *:443>
  ServerName example.com
  ServerAlias www.example.com
  DocumentRoot /var/www/public_html/example.com
  SSLEngine on
  SSLCertificateKeyFile /path/to/private.pem
  SSLCertificateFile /path/to/cert.pem
  SSLProtocol all -SSLv3 -TLSv1 -TLSv1.1
  Protocols h2 http/1.1
</VirtualHost>

References
https://www.howtoforge.com/how-to-enable-http-2-in-apache