Hi @hangtotnenmua,

Thanks for reaching out to us.

If you want to delete only specific applications, you can delete the applications just like deleting a regular post in WordPress from the administrative Dashboard.
Suppose you want the applications in your site to be automatically deleted based on an interval, you can use Auto Delete Applications – an add-on for WP Job Openings for doing the same (https://wordpress.org/plugins/auto-delete-applications-add-on-for-wp-job-openings/).

Regards,
Vidya K V