Help file stl

i need some help to get this fixed to simple.
now its al little parts.

can someone fix this form me,

i deleted the original by accident.
the side is normal smooth. and way less polygon or how you call it?

thanks for the help
file1

i just remade the design, but im still wondering if its possible

i also saw you can rename it to zip, and then the only file i see usefull
is with .model. but can we do something with that.

thank you

Your overhangs are unsupported and cantilevered too far. Lots of ways to fix: wider line width, shorter layer height, use supports, etc.

support is been used, see image?
the 1 images that was the support?
all overhang was supported?

also its bambu filament , and i used the correct standard settings, so why i not to change that?

not is need
thank you

greetings