How Oracle9i Form Builder interact with Html waebpage??

technical environment : (Forms [32 Bit] Version 9.0.2.9.0), oracle JInitiator Version 1.3.1.9, WebUtil Version 1.0.2(Beta), window xp service pack 2 build 2600, Internet Explorer 8).

i m looking for how form Oracle9i form builder:
pass values to a html web page
and
execute a trigger written on a button as well in a html web page.

In detail:
there is web page called metar_taf.html has:
metar text item which contains airport code fox example (OLBA, LCLK, LFPO ....)and
button called submit, if it' is clicked all the metars messages for the airport having a code mentioned in the metar text_item are displayed in a generated html file.
also
i create my form called read_web_file.fmb

My question is how i can through my fmb form:
set metar text_item found in metar_taf.html by the airports code (OLBA, LCLK,...)
and
run the trigger already written on the button submit found in the metar_taf.html to generate new html file that contains all airport code messages for (olba lclk....)

save the generated html file which contains the airport messages as pdf extension

Any help i appreciate it.