Ask HN: Learning webdev

If you had to re-learn all that you currently know about webdev, what would your path toward re-acquiring that knowledge look like?

For example, which toy projects would you build as a way to learn it? Which tools would you focus on learning, and in what order? Which resources would you study?

To make this question interesting, assume that the learner is a competent hacker who wants to immerse themselves in webdev as quickly as possible, but knows nothing about modern CSS practices, which devtools to use, or anything else that you'd learn after working in the field for several years.