Can't help anybody , please?

@Willr => Thanks for your reply.

Yes, I don't see the new 'User Defined Form' option in the 'Create Page' dropdown in my sitetree.
And the three things you said are already done(attached screenshots). But in vain, brother.

How can I do for that?

Ya ....
It's ok with userforms/code/UserDefinedForm.php.
And I didn't create any tables in my database yet , so I think my database won't have any UserDefinedForm related tables.
I reinstall that module , rebuild database but it still haven't appear in my admin page.
(Most of silverstripe tutorials aren't complete without userforms module , so I can't keep studying tutorials. )

Is there any possible facts that I have to check?

Thanks again...

Ya .. you are right,brother.
It happens cause of permission.(Thanks for your help )

Now, I see UserForm Page type in admin page but I create that kind of page type ,the error shows "The CMS requires that you have JavaScript enabled.".(I searched "how to enable Javascript" , but I didn't see any page writing about that.)
So could you please tell me how to enable Javascript?

In _config.php,
"
<?php

LeftAndMain::require_javascript('userforms/javascript/FieldEditor.js');
LeftAndMain::require_css('userforms/css/FieldEditor.css');

?>
"

But there is just only one .js file(userforms/javascript/UserForm.js) in my folder.For CSS, it's ok.
Is it default?

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