You can, but there is no form of exporting your handwritten notes. There's also sort of a tendency to "bend" what you've just written a bit after you lift your stylus. Like it's vectorizing and slightly correcting the path you just drew.
I have had moderate success using the built-in Scribble feature to convey my handwriting into text in the main editor. It's not super great but is serviceable. It's real opinionated about when and where new paragraphs should appear.