Install php 7 on centos7
yum install epel-release
yum install remi-release
yum install yum-utils
yum-config-manager --enable remi-php70
yum-config-manager --enable remi-php71
yum-config-manager --enable remi-php72
yum install php php-mcrypt php-cli php-gd php-curl php-mysql php-ldap php-zip php-fileinfo
php -v