To convert your handwriting, whether your content is a piece of text, math or a diagram, double-tap anywhere on your block or object, or tap 
at the right of the conversion preview, then tap Convert.
Handwriting conversion is not available in Freeform sections or pages but this can be copy/pasted into regular Nebo pages and then converted.
Note: It is not possible to convert only a part of a block or object. If you convert some text accidentally, tap 
in the top right to undo the conversion.