NO your printer won't print stl files.

You need a program that takes the .stl file and slices it into gcode specific to your printer and that particular print job.

what program did you use to convert the stl to gcode ?

okay your coccoon 3d printer looks like a wanhao duplicator i3.
Be interested to see if aldi sell them in the uk.

for slicer purposes you should set it as a prusa i3 - try using Cura as a slicer and either prusa i3 or wanhao duplicator i3 as the model.
Well if you got it from aldi - then you should already have cura. Did you actually read ANY part of the startup guide or manual ?
Here's a link to cura anyway :-)
https://ultimaker.com/en/products/cura-software