Adding modules to php 5.6

Good morning
this is my first time with Virtualmin/PHP, so please be patient!

I’m going to install nextCloud. I installed a virtual server for hosting nextCloud and installed successfully PHP 5.6.
Now, nextCloud installation procedure ask me to install some PHP modules:
“PHP module mb multibyte not installed”
“PHP module GD not installed”

I tried install them via Virtualmin interface, but no success.

How can I install these modules (and other if needed)?
Thank you

Hi, you did not said what distro you are running on but in case of debian you can list all available php modules like this apt-cache search --names-only ^* php5- and then install those you need like apt-get install php5-gd php5-mysql …and so on.