You can remove comments individually or in bulk within WordPress.

Log in to your WordPress admin area.

Go to Comments > All Comments

Filter comments based on the following:

        All
        Pending
        Approved
        Spam
        Trash

After filtering comments you can delete them individually or in bulk:

To remove them individually:

Highlight a comment with your mouse cursor

Click Trash

The selected comment will be moved to the trash.

To remove in bulk:

Place a check in the box next to each comment you wish to remove

Select "Move to Trash" from the "Bulk Actions" drop-down

Click Apply

The selected comments will be moved to the trash.