hi,
I need email notification, email will be automatically sent email to user when ticket will be change
You can do that with a Toolset Form, where you decide when the email is sent to whom and with what content.
More information can be found here:
https://toolset.com/documentation/user-guides/automated-email-notifications-with-cred/
Basically, the Toolset Form that either creates or edits the post "ticket" will have a Notification (or many) attached as per above DOC's steps.
Then the form will trigger that notification when the precise events take place that you set in the Form's Notification to trigger the email.
You can, for example, set the notification to send only if a given field is set to a given value or any other imaginable condition. There is a GUI just under the actual Forms Editor in Toolset > Post Forms > New that allows you to create all those things easily.
Please let me know if you need more details in a particular detail of notifications.