Seems like it is going to take a long time to get to a fully functional game if this is the second article and they're only just calling SDL_CreateWindow.
But you are right, it'll take a daaamn long time. I've the third and the forth parts almost ready, covering the engine architecture itself, the private scene scope and the image->texture->sprite stuff but i havn't started yet with ECS, fs, configurations, physics, networking... this field is really extense.
It's four and a half years into Handmade Hero at this point :-)