Not able to reorder the date in the custom content section

The client was using an Accomplishment content section with their custom field without any seeded field. So whenever they add any data in the content section the system automatically shows the last update date without any sequencing order, and they want to do the date sequencing, I did some research on that section and found that in order to use date sequencing, we also need to use the Date Accomplished field and that is a seeded field, so whenever we will enter any data in this section and all the record will be show based on the date sequence.