Hi, what type of personal projects are you working on? I started learning c recently and I want to learn embedded development, but I don't know where to start or how.
For myself, after getting something simple like the above working, it was a gateway to much more experimentation of further possibilities, and ultimately I ended up making an interactive shell [1][2] with some built-in utilities and text games I also wrote that runs on a variety of AVR microcontrollers (those very same Arduino boards I had when starting out).
[1] https://community.atmel.com/projects/avrsysh-systemshell-som...
After 38 years of programming in C, I'd instead recommend exploring CircuitPython.org from Limor ("Lady Ada") Fried based on the work of Damien George. Also recommend starting out using one of her kits https://www.adafruit.com/category/116 and avoiding rechargeable batteries (unless they're NiCads) while keeping your USB power adapter on an easy-to-reach power strip for a while.
Even back in the day, I would have recommended new embedded systems developers start with FORTH or BASIC (PEEK and POKE yoh) ..or if it was a serial/UART-controllable device, Phillippe's insanely great Turbo Pascal --that is unless you had already written a lot of applications in C and maybe a few operating system hacks or device driver mods too.
I think the most important thing to do figure out what you actually want to make. Any microcontroller SDKs are going to be at least usable for most things.