Sripting a modelling tool?

Trying to script a modelling tool with python,
what should i look up? Other than python scripting?

How do i draw and snap to triangles in 3d xyz space in a single camera view?

Not sure what you mean by “snapping”. If you mean mouse cursor snapping (to vertices and stuff), that’s not directly accessible from Blender’s Python API. To get that kind of snapping you would have to code your own snapping system or use macros like Okavango did with the NP add-ons. For creating geometry I’m not sure, maybe the BMesh module?