How to Run PHP Scripts in *.html or *.htm Files
Question One: Does my web host support PHP?
<?php echo "hello world"; ?>
After saving the file please upload it to the root directory of your webspace. Open your browser and direct it to the file you just uploaded: "http://www.your-domain.com/phptest.php" (Needless to say, you should use your own domain here...)
It's the moment of truth now. What does the browser say? If you see the words "hello world" everything is fine, PHP is working. However, if you don't see these words please contact your hosting provider because PHP is not working (yet). Most hosting companies provide packages including PHP. So perhaps you just have to switch to another hosting plan.