To convert a "thread" feature to a true realistic 3D model of a thread (e.g. for 3D printing) you can use the free plugin "ThreadModeler" (coolOrange Thread Modeler).
Download and install the add-on application for Inventor 2020, 2019, 2018, 2017, 2016, 2015, 2014 and 2013 from Autodesk Apps.
For newer versions, use the online tool ThreadModeler.com and upload your IPT model with "cosmetic" (texture-based) threads to convert it to modeled thread. Or use the Tip 12962.
Another option is to use the application Fusion 360 (e.g. as a part of Product Design & Manufacturing Collection).