Depends on the category you are publishing and how you want it to work.
I want to post it on themeforest but I just want to make the design I don’t won’t to create php files I mean I create the design and the user completes the server side himself ?
You don’t have to even design, you can ask the users to design it, too – Sorry but I had to say
If you’re using a theme based on PHP, you have to create the files as well. But if you’re creating HTML theme, as long as you’re not using the contact form or etc, you don’t have to create any PHP files.
If you’re creating PSD template, you don’t have to create HTML/CSS as well
The “PHP Files” features under the “files” while you’re submitting the theme, it’s optional.
It seems either you didn’t read or you didn’t understand the link (URL) I have posted few weeks ago on your other thread(question) about the submission guidelines.