@sharonking5 , we don't have our welding courses completely online, but every welding course on campus uses Canvas for all of their quizzes and assignments. We also have HVAC courses using Canvas as well!
Some of the content that we include in these courses are video (great for demonstrating hand skills and other important information), handouts, study guides, and links to external resources.
Overall from working with the Instructors for these courses I'd treat it as any other online course. Focus on what the students need to know and the best way to deliver it in an online environment. For Welding I'd say the video is probably the best thing for students. It allows them to watch different techniques, etc as many times as they need. No, it's not a substitute for doing it themselves, but it's great for demonstrating things. I also bet that it would be great to illustrate safety features/concerns. I'd also recommend using the actual welding Instructors when creating the video. Students like seeing/hearing their Instructors and tend to pay more attention.
Hope this helps!