There has a proper way to implement SDL for os development?
By “os development”, do you mean, port LibSDL to a different OS, or something else?
If you’re looking to port LibSDL elsewhere, there is a README-porting.md document in SDL2’s docs/ directory. I am unsure how up-to-date it is, but at a glance, much of it looks correct.
For reference, the latest copy of README-porting.md can be found at https://hg.libsdl.org/SDL/file/tip/docs/README-porting.md