This question already has an answer here:
From what I've read before, according to Jewish belief, if a non-Jew follows the Noahide Laws, he/she will not suffer in the afterlife. Are there any verses in the Torah/Tanakh to support this?
If anything, I may have seen a verse in the Tanakh which said something like "Believe in the Lord and the prophets...". I don't remember the exact verse. But I don't know. Maybe this law only applies to Jews.