Set the challenge to create my own 3d engine from scratch. Where to start?

Im on windows i would like to have a .exe file which is a 3d viewer, similar to blender. Which language do i code it? Which libraries would i…

If you are using C, you could consider SDL 3 as a base library.

Not a recommendation though. Just saying you can do so.
It has all the basic stuff: V-Sync, audio, input device handling etc.

Almost forgot to add… It also allows you to easily add stuff with Vulkan, OpenGL etc.