sudo apt - get install php libapache2 - mod - php code example
Example 1: install php 7.1 on ubuntu 18.04
sudo apt install php7.1 php7.1-common php7.1-opcache php7.1-mcrypt php7.1-cli php7.1-gd php7.1-curl php7.1-mysql
Example 2: ubuntu install php 7
sudo apt-get install php libapache2-mod-php