I want to limit to access to my theme and plugin until verification.So, I want to make premium plugin and theme.If user doesn't write true code, my plugin and theme musn't work.How can I do it? Can you give a real snippet? Or good paid solution for it without commission method?
This is not how premium plugins usually work, because it’s generally agreed that it’s not legal, as it violates the WordPress license agreement. Code cannot be made non-functional in that way.
Instead premium plugins typically charge for access to a download, as well as support and updates. To only distribute updates to licensed users, you would need to integrate any code provided by the platform you are using to sell the plugin. For example CodeCanyon and the Easy Digital Downloads licensing extension both provide APIs for checking license. You would need to consult their documentation for specifics (they would be off topic here).