They should follow in the ancient traditions of Judaism (the Torah) exactly.
That being shomer mitzvot (a guardian or keeper of the commandments) is the most important thing, and that Orthodox Rabbis are the source of authority about how to do this.
No.
Note first that Judaism as a whole is more about what you do than what you believe. Orthodox Jews believe that Jews are obligated by all 613 mitzvot (commandments) in the Torah and should act accordingly, using the traditional interpretations of these mitzvot as explained by Orthodox Rabbis.
Yes, non-Orthodox Jews can become Orthodox by becoming more observant. Non-Jews can become Orthodox Jews through Orthodox conversion.
Orthodox Jews are strictly observant. Hassidic Jews are even more strict.
Orthodox and Ultra-Orthodox Jews are strict followers of Jewish law.
Unfortunately, in Israel, only Orthodox Jews get all the special privileges.
They are Jews who keep the Torah.
Orthodox Jews or Torah Jews.
Haredi Jews are ultra orthodox Jews found around the world.
Symbols do not destinguish Orthodox Jews from other kinds of Jews. Orthodox Jews are distinctive in that they adhere to the idea of the of the binding nature of Jewish law.
In South Africa, like most countries aside from the USA and the UK, the Jewish communities are overwhelmingly Orthodox. Whether or not a person who attends an Orthodox Synagogue is Orthodox in his "non-synagogue activities" is purely up to the believer. So, some members of the Orthodox community may not actually be observant Jews and would appear like Reform Jews in the USA. However, they would not call themselves Orthodox, but Jews who happen to belong to an Orthodox synagogue. Actual Orthodox Jews in South Africa would be indistinguishable from Orthodox Jews in the USA.