How do I use workspaces while I'm watching the lecture so that I not miss anything?

You could launch a workspace window by clicking "launch workspace" on the bottom right corner of the video screen. Or in the section below the video where you see the teacher's notes, downloads, etc, there is a tab called "workspaces." You could launch it from there as well. Another way to launch a workspace is by clicking "Workspaces" near your profile picture ton the top right corner of the website and selecting a previously opened workspace.

Hope this helps!

Awesome! Good luck on your journey, Ephraim!

I know the question is a couple of months old, but this is what I do if I don't have a second monitor available...

1. Open Treehouse in a browser.
2. Launch Workspace in a separate window.
3. Make sure both windows are minimized.
4. Swipe the Treehouse window all the way to the side, so that it fills up only half of the screen.
5. Swipe the Workspace window all the way to the other side, so that it fills up the other half of the screen. You have to make sure that you swipe all the way to the side, even if it looks like you're swiping off the screen. If not, you'll just maximize the windows. You can resize the windows to whatever proportions you prefer, of course. I like 50/50. I often toggle the Treehouse window between fullscreen and 50%, depending on if I need to use Workspace or not.