The trial is fully functional but expires exactly 30 days after installation.
Revit 2020 introduced several major updates that are still relevant for BIM coordination today: autodesk revit 2020 trial version download
The ability to import PDF files into Revit and snap to the data within them. The trial is fully functional but expires exactly
Enhanced support for feed-through lugs and electrical homerun wiring. Important Trial Limitations autodesk revit 2020 trial version download
You cannot "reset" a trial on the same machine once it has expired.
Students and educators with a verified Autodesk Education account can often access a broader range of older versions, including 2020, for educational use. System Requirements for Revit 2020