Follow this guide
https://www.howtoforge.com/how-to-install-zabbix-6-on-debian-11/
In case, if below step failed like file/folder not found.
zcat /usr/share/doc/zabbix-sql-scripts/mysql/server.sql.gz | mysql -u zabbix -p zabbix
Change to below for this step.
zcat /usr/share/zabbix-sql-scripts/mysql/server.sql.gz | mysql -u zabbix -p zabbix
After the initial setup and first login, if the locale getting issue, go to terminal to install locale.
dpkg-reconfigure locales
For me, I selected all en_US.
After that, need to restart the apache service.
systemctl restart apache2
In addition, I have change the URL from http://ip/zabbix to http://ip/. To do this, just change the DocumentRoot from /var/www to /usr/share/zabbix in Apache. Also, I have enable https by Let’s Encrypt.
Done.
Remark: Remember to set Cloudflare Tunnel afterwards.
Refer:
https://www.howtoforge.com/how-to-install-zabbix-6-on-debian-11/
https://www.zabbix.com/forum/zabbix-troubleshooting-and-problems/427991-zabbix-giu-broken-no-languages-and-web-interface-errors
https://www.zabbix.com/forum/zabbix-help/28949-change-the-apache-path-to-zabbix
https://www.digitalocean.com/community/tutorials/how-to-secure-apache-with-let-s-encrypt-on-ubuntu-22-04