Upgrading to PHP 5.6 and MySQL 5.6 on a CentOS 6.8 system (Multiple PHP Versions)

Hi there,
I am using Centos 6.8 with PHP 5.3.3 and MySQL 5.1.73 and I want to install a second php version so I can choose the newer one only when I want to force PHP 5.6 in specific servers.

I have found the links listed below but I still don't understand how to do it correctly, as the commands differ in the two links.

Can you please point me to the right direction on installing PHP 5.6 as a second instance?

I also want to achieve the same scenario in MySQL, as some sites need MySQL 5.6 or greater in order to work properly. Can I do it like with php?

The links are these:
https://www.virtualmin.com/node/39002
https://www.virtualmin.com/documentation/web/multiplephp
https://www.softwarecollections.org/en/scls/rhscl/rh-php56/

What I have done so far (but don't know if it's the right way to do it, but php appears as a second php version in virtualmin):

sudo yum install centos-release-scl
sudo yum-config-manager --enable rhel-server-rhscl-7-rpms
sudo yum install rh-php56
scl enable rh-php56 bash

I would be more than grateful if you could help me out on this.

Thanks in advance