<p>I work with Fusion360 for designing lots of things. Recently I learned how to work with parameters that I can easily modify all at once, allowing to pretty much make easily customizable pieces.</p>

<p>Now, Thingiverse wants customizer pieces in the shape of <code>.SCAD</code> files, and some people just can't work with Fusion360 (<code>.F3D</code>) or proper <code>.STEP</code> files that can be imported by most CAD programs.</p>

<p>I have no experience with OpenSCAD. Can I import my <code>.STEP</code> into openSCAD, retain my parameters and export it as a <code>.SCAD</code>, and if yes, how?</p>

No, you cannot import STEP nor Fusion360 files in OpenSCAD.
OpenSCAD
currently supports
:
3D formats
STL (both ASCII and Binary)
OFF
AMF [Note: Requires version 2019.05]
3MF [Note: Requires version 2019.05]
2D formats
DXF
SVG [Note: Requires version 2019.05]
Other
CSG can be imported using
```
include<>
```
or loaded like an SCAD file, PNG can be imported using
```
surface()
```