Polygon Reduction

Are there any polygon reduction tools in Blender?

there is a poly reduction script

There’s also the Decimate object modifier.

What is the the Decimate object modifier?

press F9 and look in the “modifiers” panel and hit the add modifier dropdown.
easy to use, just adjust the number button till you see what you like. hit apply if you feel like it.
works in object mode, not edit.