Why I can't open the PDF documents or catalogs. Thay show that I need a
licence or something like that. I could open PDF on my phone and in the
computer I can't.
First, to open *any* kind of file you need to have an appropriate
program installed that knows how to do that. For a pdf file, the most
common program is called Adobe Reader, but there are several
alternatives, such as Foxit. Do you have such a program installed? If
so, which one?
Second, as always, when you are looking for help with a problem, and
you get an error message, you need to provide the exact verbatim text
of the message. Just "I need a licence or something like that" is not
really good enough information to diagnose what's wrong. Also what
program is displaying the message?