You will receive a six digit confirmation number after you NETFILE. Go back to the File section and make sure you completed the NETFILE process - you'll see the confirmation number there.
Here's also some information on how to check the status of your return with the CRA: https://support.turbotax.intuit.ca/turbotax/en-ca/faqs/How-do-I-check-the-status-of-my-tax-return-or...
