In QuickBooks Self-Employed, you can find your 1099 from the Tax forms tab when you go to the Clients menu. Please take note that the form will be available after your employer or client submits your 1099-MISC to the IRS.
Here's a sample screenshot of what it looks like:
You can also read these articles for more information about 1099s and the tax guide in QuickBooks Self-Employed: