Use the Help Button!
There are two forms of Help available on to students when using Canvas. One is the Help icon on the front page of every canvas course. This button will lead you to this Help Course where you can poke around to find the answer to your question. It may lead you to the Canvas student help pages with thousands of answers to questions, or it may contain the answer right there on the page for you.
The second Help button is on the black navigation bar on the left of the Canvas window as the last icon. When you select that Help button among other help sources, you can select "Ask Your Instructor a Question". Select which course you need help in from the drop-down window at the top. All your courses will be listed. Type your message in the box and send it.