Are you trying to build category editor? Then it is simpler to make a list&search type that will list all categories with redirect to edit form. 

To do what you would like to do you would need some custom javascript that would open category form in popup after user has selected some category.

Oh ok thanks.

So I was able to list all category but now, how can I open the edit form when I click on them ?

You need to go to the list (or item, depending on the template chosen) tab of your search&list type and then add link (button 2), where you select Seblod->form.

Oh it works, one last problem, data isn't submited to the form, when I click on a category with a title and a description data isn't send to the form how to fix that ? Thanks !

When you load a form with some id data should be loaded too. But please note categories do not use article title, they use category title field, you should have them in form if you with to see them.

What's wrong so ?

Here is how I list & search :

And here how I display my form :

So, my category are nicely listed, but when I click on one category the form appear with no data inside

Thanks for help

Open categories search/list type, go to item tab. There click on 2 - Link and set link to Seblod-Form. Then click on + and  set values there to inherited / inherited / auto / auto