I've been re-learning some basic concepts of C. What next?

So far, I've followed a simple Tor interceptor tutorial on YouTube, while strictly adhering to C2x with every warning flags enabled - not that it is the optimal way to go about learning the language.

I may have, or may not have inadvertently used improper C2x, but I've used typedef aggressively to slightly mimic Golang.

Almost a year ago, I had blindly translated a C++ Vulkan tutorial to C, and I didn't understand a single thing about anything graphics-related - framebuffer, swapchain, etc.

Now that I am learning it again from scratch, I also wanted to know what to learn next, as well as some of the job opportunities that I can explore.