Set up a new PHP environment
Open the Elastic Beanstalk console.
You can see any existing application environments you have already set up.
Select 'Create New Application'
Name your applciation an then decide if its to be a web server or worker environment
Select Predefined Configuration: PHP
N.B. If you don't want the default PHP version (e.g. PHP7 which removes some functions like older mysql functions) then you need to select the "Change platform version" link in the text that appears!!
Your files
You can simply zip up your PHP etc files and provide this as the source. The URL of the files is just the URL shown once the environment is created + the file URL, all very simple as you'd expect.
To provide a new version of the files in an existign environment
Press the Upload and Deploy button