This course takes is specifically designed for developers that either don't have any previous experience using an Integrated Development Environment (IDE) tool or experienced IDE developers new to Intellij IDEA (e.g. experienced Eclipse developers).
With that said, even if you're an experienced Intellij IDEA developer you might still get something out of the course. This is specially true since this course is (almost exclusively) based on version 2019 which introduced features that you may not yet me familiar with. So please still check it out!
Also, no particular programming language knowledge is assumed since Intellij IDEA is pretty much language agnostic and supports many different programming languages.
Sections I, II and III are mandatory and must be taken in order.
Section IV is specifically designed for experienced Eclipse developers interested in a quick migration path to IntelliJ
The rest of the sections (V, VI, VII and VIII) can be taken in any order as they're self contained. I highly recommend that you still taken them all, particularly if you don't have any previous Intellij IDEA experience.