I am taking the position that perhaps the Torah does contain narratives that are not scientifically correct, such as the creation and early human history narratives found in the first 11 chapters of Bereshit. Something to have in mind before you give your answer is that Rambam’s 13 principles seem to say that we should believe that God gave everything in the Torah to Moses (I suppose that would even include some of the narratives that are not scientifically factual), and that nothing in the Torah changed or will ever change. So now with that in mind: Would believing that some of the narratives in the Torah are not scientifically factual no longer make me Orthodox and brand me as a heretic, or would I still remain Orthodox?
The Torah, the Talmud and Chazal do not use the artificial label "Orthodox" or recognize subcategories of Judaism, it is just one religion. And you remain as Jewish as the rest of us even if you question and doubt. Yes, events described in the Torah are ofttimes inconsistent with laws of nature as we know it, or current scientific knowledge, and could only have occurred miraculously. We believe in miracles, and that things happen beyond the rules of nature, Shelo B'derech Hateva. Don't label or brand yourself if you do not yet see the miracles in every day life.
אם אין יראה, אין חכמה
If there is no fear, there is no wisdom.
(משנה אבות ג יז)
וְעַתָּה֙ יִשְׂרָאֵ֔ל מָ֚ה יְהֹוָ֣ה אֱלֹהֶ֔יךָ שֹׁאֵ֖ל מֵעִמָּ֑ךְ כִּ֣י אִם־לְ֠יִרְאָ֠ה אֶת־יְהֹוָ֨ה אֱלֹהֶ֜יךָ לָלֶ֤כֶת בְּכׇל־דְּרָכָיו֙ וּלְאַהֲבָ֣ה אֹת֔וֹ וְלַֽעֲבֹד֙ אֶת־יְהֹוָ֣ה אֱלֹהֶ֔יךָ בְּכׇל־לְבָבְךָ֖ וּבְכׇל־נַפְשֶֽׁךָ׃
All that is demanded of a Jew is that they fear the ultimate consequences of their actions and beliefs. In regards to this example: They must fear the possibility that when they will face the ultimate judgement in front of their Creator, He will reveal to them exactly how all the stories in the Torah were literally and scientifically true and they will immediately feel drenched in shame for having lived a live that dismissed that possibility. Simultaneously, they must fear the possibility that on judgement day, their Creator will reveal that the stories in the Torah were not intended to be taken literally and they will feel ashamed for not having given that possibility proper consideration.
To answer your question: If you are dismissing entirely the possibility that the stories in the Torah are scientifically accurate then you have strayed from the path of what is fundamentally required of a Jew.
However, if you just mean to say that given the context, arguments, and possibilities you have been presented so far, you lean towards the understanding that the stories in the Torah are not meant to be taken literally, yet remain open to the other possibility, and fearful that, indeed, the reverse may be true then you are well within the confines of Orthodox Judaism.
Although as others have pointed out, there exist people who consider themselves Orthodox Jews yet do not demonstrate Yiras Shamayim, and others who do, yet do not identify as Orthodox.
One of the Rambam's 13 principles of Jewish faith dictates that the Torah was given by G-d to Moses and is divine.
Now, use your logic - if G-d wrote the Torah would He put false information in it, could He make mistakes?
G-d doesn't make mistakes. Since G-d makes no mistakes, there are no mistakes in the Torah and everything written in the Torah is 100% true.
To say that there are "mistakes" or "inconsistencies" in the Torah implies that's it's not divine. This is already a violation of the Rambam's 13 principles.
Nevertheless, if it seems to us that there are scientific "inconsistencies" in the Torah then either scientific "findings" are incorrect (for instance, carbon dating which is a complete hoax) or we interpret Torah incorrectly.
But never can the Torah and science contradict each other (real objective science, not speculative science like carbon dating which is based on assumptions about the decay rate).
Therefore, an "Orthodox" Jew may not believe that there are scientific inconsistencies in the Torah. Rather, he interprets the Torah incorrectly, or scientists are incorrect.
It's not possible that there are mistakes in the Torah. Anyone who believes so is a kofer because he violates one of the Rambam's 13 principles.