Notes:
Design your keychain in TinkerCAD
Export your TinkerCAD to an .STL file.
Use a PC, not a Chromebook to access Prusa Slicer software.
Import your .stl file into Prusa Slicer software.
Select 0.30mm Draft
Select Prusa PLA for the filament setting.
Be sure to choose Prusa Original i3 MK3 (.4mm)
Convert your .stl file to a .gcode file by clicking "slice now" then "export gcode"
Name your file so you can easily find it, then save to an SD Card (you will need to use a USB to SD card memory reader).