A simple way to update your php to 8.0 on CentOS7

1. Uninstall your current php and its modules

sudo yum remove -y php php-*

1. Add remi repository

sudo yum install -y https://rpms.remirepo.net/enterprise/remi-release-7.rpm

1. Install php 8.0

sudo yum install -y --enablerepo=remi-php80 php

1. Confirm the php version

php -v
PHP 8.0.0 (cli) (built: Nov 24 2020 17:04:03) ( NTS gcc x86_64 )
Copyright (c) The PHP Group
Zend Engine v4.0.0-dev, Copyright (c) Zend Technologies

5.Install necessary php modules