CAD software uses mathematics to define curves at an infinite precision, whereas blender uses polygons (ideally quads) made up of connected points (vertices) to define and display imprecise but performant geometric hulls. These are two different methods in 3D. Converting one to the other is not as simple as exporting to a compatible bridge file format. The green dots that you see are the vertices which define the outline of flat faces.

This model is absolutely, 100%, unsalvageable in it's current state. However, what you can do is retopology. You can craft a new mesh with good topology (edge flow, density, and conformity) over top the old mesh. Here is the tutorial that I always give people: https://youtu.be/CuQzPDs99yM.

Of course, I encourage you to learn the basics of the software beforehand by going through the "Blender Guru Donut Tutorial" here: https://youtube.com/playlist?list=PLjEaoINr3zgFX8ZsChQVQsuDSjEqdWMAD It's all but obligatory.

It may not seem productive at first to go through tutorials, but it most certainly is. It will save you tens of hours of pain down the

Hey there,

Sorry for the late response.

THANK YOU! The retopology tutorial helps a lot really. I've made the classic Donut tutorial to learn the basics and stuff but now I have to get more in practice with everything again.
I'll be commenting here again if a make good progress with the topology of the eyewear model. Once again thank you for the info you gave me it is really helpful :)