teaching the names of countries needs fixing

I complain that the manner and method for teaching the names of countries is named differently from autonomous names and not using the name which the country's inhabitants autonomously used for example "norg" is how the people who live in norg call their land so we should teach in big letters name "norg" and only in parentheses the old altered name norway.
similarly for "nihon (japan)" and "z-hon guo (china)" and "hangook (south korea)] so both answers should be good and valid while upgrading the method of teaching the autonomous name of each country.
we would not ignore "united kingdom" calling it norg or any other different name, because that is not the name. similarly deutchland in big letters we should teach how the locals say their country.
brazil or brasil??
such innovation is proper to prefer the name used/given by inhabitants. for example the local inhabitants in "deutchland" call their country deutchland so we should prefer that name in big letters on map with only parentheses for the altered name germany.
similarly the locals name their country hangook that should be the preferred name in big letters and only in parentheses the altered name korea.
similarly prefer the name of local inhabitants "nihan in big letters and only parentheses japan"
and each country that name which local call their own country because we find often inhabitants have different name which is the true name established by the autonomous people to name their country. this should not be ignored. on tests both names as correct while upgrading teaching in big letters the name given by the inhabitants of each place.
similarly z-hon guo in big letters and only parentheses for altered name china.
less urgent than the country names is also to fix in stages names such as yangtze river is named by locals a different name chang-jian  so the name should be taught chang and in big letters.
some noticeable differences:
Norway= Norge
Denmark = Danmark
Iceland = Island
Germany = Deutchland
Spain = España
Italy = Italia
 also improve remove all country names from shared water regardless of country equally for example no gulf "of mexico" instead see suggestion below and similarly NOT sea of china/japan equally for any country name because the water must be shared.
instead name the gulf by the land which separates it without name of government for example "gulf of key west not a country. no indian ocean that is country name and ocean must be shared instead asian ocean a name which includes sharing. similarly the sea west from nihon (japan) asian sea in contrast to water beside china simply part of pacific ocean no separate name because of country name and not separate. similarrly most seas can and should be rmoved and so large a ship in distress must give more precise location than "sea of japan" anyway so replace and fix.
in other words, I complain that teaching names of countries in english are taught different from the names which the local government has chosen. for example true name is united kingdom so calling it hangook is not what the government decided the name was. it is simply wrong and ignores the real name. similarly when educating we should fix that the main name is the true name "Norg" in big letters and only in parentheses "norway" and same for hangook and nihon and deutchland as the main name. similarly "Z-hon Guo' main name for china. and making the effort to gather data and teach the correct name of each country. this is more urgent than fixing river names such as changjian instead of yangtze (which should also be fixed at a later stage) while urgent is for the country names.
the other issue is also a  complaint because name shared water sea "any name linked to any country" so remove equally: no gulf of "mexico" that is a country no sea of china/japan equally from all such seas. no ocean indian etc. instead "asian ocean" and for china coast simply part of pacific and for sea between japan and korea asian sea etc. this an improvement yet most urgent is teaching the correct name such as norg and deutchland instead of different names, which were altered "norway" and germany which can be "also correct" but not the main name taught because we should not making a different name the main name.