Some 10 years ago I have been programming with php within web pages, and there was never any problem. Now, trying it again, I do encounter a problem. Php does not work. The simple function

echo “Hallo World”;

Does not work – nothing appears in a browser. In the blueFish editor, the first line appears underlined red, an indication that the statement is not recognized by Appache.

The following packages are installed and activated:
apache2 version 2.4.23-31-1
apache2-mod_php7 version 7.0.7-52.1
php7 version 7.0.7-52.1
OS is SUSElinux version 42.3
all software has been downloaded from the official openSUSE repositories.

Is there anything else missing, or do I have to do something about the configuration settings?
I did not find any clue on the intelligent web pages.

Any help would be highly appreciated.
Thank you.