Cannot use DomPdf because files are missing

Good day,

Some days I was suggested to use DomPdf in my website for creating PDF files.

I downloaded it from GitHub: https://github.com/dompdf/dompdf, copied it to my cPanel and unpack it there.

After making a test.php file with the first sample code and opened it with a browser, I got a missing file warning message for dompdf-master/lib/php-font-lib/classes/Font.php, from dompdf-master/dompdf_config.inc.php on line 332.

Checking dompdf_config.inc.php, lines 330 - 333 are:

 if (DOMPDF_ENABLE_AUTOLOAD) {
 require_once(DOMPDF_INC_DIR . "/autoload.inc.php");
 require_once(DOMPDF_LIB_DIR . "/php-font-lib/classes/Font.php");
 }

But when checking dompdf inner directories, within php-font-lib there is nothing, so the error message is right, there is no classes directory nor font.php file there.
Looking the whole dompdf directory, there is no classes directory nor font.pdf file at all.

I have researched looking for a solution, but all point to use Getcomposer or Codeigniter, and I have no idea about them.

Could anyone point me how to get these missing files and put them in my cPanel in order I can use the library?

Thanks a lot!!