Go to your virtual machine from the Virtual Machines section on the right side of the page or from the server section of your application Overview tab.
Chose to the OPS tab
Click +Add new Package
Find the required PHP version either in the resulted list, by using the Search & enter box or by selecting the LANGUAGES tab, then click on it
Either configure the package or use the default settings then click Add Package. The PHP package will be visible in the resulting packages list and will be marked for deployment with the green switch.
To add another PHP version just repeat steps 3 - 5.
To start the deployment of all the added packages that are marked for deployment, hit Deploy Changes