Need design for a mesh editor

(While this is technically a plugin design question, I think i’d get better responses in this category)

I’ve been trying to design a mesh editor for a while now, I have some modules for working with meshes, but I’m trying to figure out how to implement the UI for verts and tris, and how to draw or place them.

I haven’t really worked with modeling software, so I’m hoping to get some tips here for designing said mesh editor.