How to reduce the number of polygons in a unit?

Question

Unity

I have a simple object (sphere) I need to reduce the number of polygons without a 3d editor.

Answer 1

I don't think it's a good idea...
You can see this article:
https://habr.com/ru/post/428796/
Keep in mind that a script for one topology may not be suitable for another.
By the way, if you still do this, you will need to study topology (science)