How to use PHP?

Question

I know a little bit html. I am learning PHP.
How to use PHP?
Do we need to install some IDE like in Python, C++ or do we need to save a text file with extension '.php'.
I tried to run sample code of lesson by writing it up in notepad and saving it both with .PHP and .html extension. None of those worked. How do I use it?

Answer 1

php works on server side so you must download xampp install and setup it
then run apache go to your browser and type Localhost it will show every files in c/xampp/htdocs
if you don't understand go and search on youtube about how to install xammp

Answer 2

Thanks, so that means I have to install some additional components.

Answer 3

had better to up and run with a linux os (like ubuntu or mint )
then install Apache server and php libs
then just code with simple editors like "vim" or "subline"

you can use phpstorm later.