I always love to see Love2d mentioned. Love2d + Lua were my introduction to game programming, and really helped me catch the "bug" for game dev.

It's a very great framework for learning the basics but will require extra work for a polished end result. The forums and documentation are a solid place to start! https://love2d.org

I also use LÖVE 2D. I like it as well (just use Sublime Text for dev, don’t need IDE), but I would guess it’s slower to get results compared to Unity.

Another code-only way is Flutter.