The first step is to go to your Inbox,
then you'll see a pencil that looks like it was writing in a square across the "All courses" and "Inbox" dropdown.
Just click it and it will show this:
Select your course, and a "To: ______" will appear right between the course and the subject. Fill it up with the name of your professor and email her/him accordingly.
Hi @goldenshteynl 
I'm wondering how you are going about sending your instructor the message.
Here's a guide for how to use the Inbox within Canvas https://community.canvaslms.com/docs/DOC-10574-4212710325
I hope it's what you are after.
The first step is to go to your Inbox,
then you'll see a pencil that looks like it was writing in a square across the "All courses" and "Inbox" dropdown.
Just click it and it will show this:
Select your course, and a "To: ______" will appear right between the course and the subject. Fill it up with the name of your professor and email her/him accordingly.
