How can i export the captivate pro ject to PDF?

Answer is simple: you cannot.

It used to be possible to export to interactive pdf, but since the Flash Player is no longer included with Adobe reader, and this method was based on SWF output, this is no longer available.

It has never been possible to export directly to a static pdf. With a static pdf I mean a digital print, which is probably how you know pdf better. It is a bit weird to ask for a 'print' of an interactive eLearning course. You can print to Word with the File menu, but you may see that not everything (there are several print templates) will be included in such a Word document. It is easy to convert such a document to pdf.