HI @raphael,
Free 000webhost is restrictive in many ways, so it is just loss of time and energy. I tried it two years back but had severe limitations.
I suggest you try in your localhost. Download XAMPP and run it in your computer. Then your computer acts like a server. You can install OJS in your computer and run as if you are running OJS in the web server.
Hope this helps you.
Best regards,