It is crucial to have realistic expectations. The HP un2420 is a 3G (HSPA) module from a bygone era. Even with a working driver, you will not get 4G LTE speeds. The driver primarily enables basic modem functions and the NMEA (National Marine Electronics Association) port for GPS functionality.
What is the of your HP laptop? (e.g., EliteBook 8440p, ProBook 6550b) Are you running 32-bit or 64-bit Windows 10? What error message or status do you see in Device Manager? hp un2420 mobile broadband module driver windows 10 upd