I am trying to add my 10 pages external PDF file in between the LyX document. But when I convert my whole file in PDF version the external file only shows its first page. What should I do now?
When you Insert > File > External Material, you should choose the PDF pages template:
Note how it mentions the option
pages=- in order to include the entire document. That is, by default, this template (using the
pdfpages package) only includes the first page. Therefore, under the LaTeX and LyX options tabs, enter
This should include the entire PDF in your document output. LyX will still only display the first page as a frame of reference.