When I took the classroom part of the Road I course, we watched a video explaining how to position yourself in lanes when riding in traffic. Nowadays, everything is available online, and I found a similar video on YouTube. It’s not exactly the same as the one we saw in class, but some of the scenes are, and it uses some of the same certified league instructors for demonstration.
If you poke around in YouTube and other places, you’re likely to find other worthwhile instructional videos. As a lifelong rider in the right lane, some of this stuff was eye opening for me. But then, I’m still a noob.