Centos

 yum install -y epel-release
 yum install -y http://rpms.remirepo.net/enterprise/remi-release-7.rpm

 yum install -y yum-utils

 yum search php74

yum install -y php74-php-gd  php74-php-pdo php74-php-mbstring php74-php-cli php74-php-fpm php74-php-mysqlnd php74-php-opcache php74-php-mcrypt php74-php-xml php74-php-bcmath php74-php-pecl-memcached php74-php-pecl-redis5 php74-php-xmlrpc php74-php-pecl-zip

service php74-php-fpm start

Ubuntu

sudo apt update
sudo apt install software-properties-common
sudo add-apt-repository ppa:ondrej/pkg-gearman

apt install -y php7.4-gd  php7.4-pdo php7.4-mbstring php7.4-cli php7.4-fpm php7.4-mysqlnd php7.4-opcache php7.4-mcrypt php7.4-xml php7.4-bcmath php7.4-memcached php7.4-redis php7.4-xmlrpc php7.4-zip