Revit was designed to use TrueType fonts (this was before Autodesk owned it) and it does not support the SHX type fonts usually associated with AutoCAD. These are in some cases 25+ years old and unfortunately for AutoCAD users - you need to change.
This can be done using font mapping if you are planning to import dwgs into Revit, But seeing as you will need to revisit your company drafting / documentation standards, now is the time to change the font across the board.
Not very helpful if you don't want to change - but that's new technology for you, sometime you have to (and should) move on.
Simon