Good projects / challenges to get better at Docker?

I'm a frontend dev. I love UX, CSS, JavaScript / React, GraphQL, Node but I've never enjoyed devops and infrastructure.

I know the very basics of Docker but I hate using it. Our pipeline at work is quite complicated so when something breaks Ive never any idea how to fix it.

What are some good projects or challenges to get more comfortable with Docker? I found Wes Bos's course great for learning JavaScript as it was lots of little tasks that got incrementally harder. Im finding it hard to motivate myself as any cool side project ideas that I have don't need Docker.