Problem converting pdfLaTeX book to LuaLaTeX

[Haines Brown]

I'm running TexLive 2022 and have not yet upgraded to 2023. 

I'm trying to convert a book written with pdfLaTeX to LuaLaTex. My 
hesitation is that publishers will not accept LuaLaTeX

In the pdfLaTeX file I have the line \usepackage{fancyheader}. When 
it is in a LuaLaTeX file I get error that the .style file 
cannot be found. Here is minimalist example:

  \documentclass[12pt]{book}
  \usepackage{fontspec} 
  \begin{document} 
  TEST
  \end{document}

  ! LaTeX Error: File `fancyheader.sty' not found.

A search on line did not indicate that fancyheader had been  
deprecated. 

-- 

     Haines Brown