The steps shown in this article will allow you to bulk unenroll multiple contacts from your sequence. If you have a tag assigned to the contacts you would like unenrolled, the best approach to unenroll these contacts would be to save a SmartList using that tag as the filter, then assign that SmartList as an auto-unenrollment filter inside the sequence you'd like the contacts unenrolled from.
For a more detailed walkthrough of this process to bulk unenroll contacts from a sequence, please see the video below.