Remi Collet published a quick tutorial about installing PHP 8.1 on Fedora, RHEL, CentOS, Alma, Rocky or any other RHEL clone.

Install PHP 8.1 on Fedora, RHEL, CentOS, Alma, Rocky or other clone

Here is a quick howto upgrade default PHP version provided on Fedora, RHEL, CentOS, AlmaLinux, Rocky Linux or other clones with latest version 8.1. You can also follow the Wizard instructions.   Repositories configuration: On Fedora, standards repositories are enough, on Enterprise Linux (RHEL, CentOS) the Extra Packages for Enterprise Linux (EPEL) repository must be configured, and on RHEL the optional channel must be enabled. 

Install PHP 8.1 on Fedora, RHEL, CentOS, Alma, Rocky or other clone - Remi's RPM repository - Blog