To create a new Task through a job, in the Web Portal go to Jobs > Job Type Templates > Select the Job type you want to create tasks with.

You can choose whether you would like a Task to be created through a Job Status Update, or a Future Reminder.

When creating either of these, select Task in the Communication type.

You can then fill in the information that you would like to have applied to the new Task, and Save.

This Task will then be created when the Job meets the requirements you set up for creating the Update or Reminder.