1. You've already got DM because everything except Oath says "Completed". Check
ECAS
2. You'll see it when IRCC update the status dashboard with the oath notification. This might take a while. To avoid disappointment, expect it'll take a couple of months from now to see the oath notification. However, it could happen much sooner than that.
3. Currently, oath dates are being scheduled in October and November for 2020 applicants. So, you'll have plenty of time from the date you are first notified about oath (on the status dashboard) to the actual oath date. You'll receive an oath email about 1 or 2 weeks before the oath ceremony.
Congrats and wish you all the very best!