change php version ubuntu

//In ubunutu
Default PHP 7.1 is set on your system and you need to switch to PHP 5.6

$ sudo a2dismod php7.1
$ sudo a2enmod php5.6
$ sudo service apache2 restart
sudo update-alternatives --set php /usr/bin/php5.6$ sudo update-alternatives --config php
$ sudo a2enmod php7.1(version)
update-alternatives --set php /usr/bin/php7.4
update-alternatives --set phar /usr/bin/phar7.4
update-alternatives --set phar.phar /usr/bin/phar.phar7.4
update-alternatives --set phpize /usr/bin/phpize7.4
update-alternatives --set php-config /usr/bin/php-config7.4
sudo apt-get install software-properties-common
sudo add-apt-repository ppa:ondrej/php
sudo apt-get update
sudo apt-get upgrade
sudo apt-get install -y php7.3


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