You have to run your .stl file through what is called a slicer program. Cura is one program and is free there are other programs also that can be used, In the program there are settings that you can change to add more or less support or none at all to the model. you can rotate the part on your build table so that you can use very little support but some models will need a lot. The plastic will bridge some distance without support. I have successfully bridged across openings as wide as 3/4 of an inch without support with very little noticeable sag in the part. Its all in the settings ie speed, heat, flow. Its really not difficult to figure out once you have done a few parts and there are lots of good information at U of YT ( University of Youtube).
