This is a cover for a typical fan for a bathroom. It consists of two parts, one is inserted into another as a cover. The bottom part is mounted directly onto fan body - by the way, you can always mount a filter right between the fan body and this bottom part, afterwards you just insert the top part into the holes from the bottom part and that's pretty much it.
The gcode files included - I use Anycubic i3 mega x, so they are for them - and sure you can create your own from STLs included. The bottom part takes ca. 4 - 4.5 hours to complete, the top part - about 22 and a half.