What is a Noahide supposed to do? Besides the 7 laws (90) I feel that G-d hasn’t thought about it. This makes me feel that there is no G-d because what if the gentiles actually start believing in Hashem sometimes.

Shalom, Thank you for your question. I’m not sure that I totally understand it though. Why “besides the 7 laws”? Would you ask “besides the 613 laws what is a Jew supposed to do?”? Why do you think that “G-d hasn’t thought about it”? (Apart from the deeper question of how you imagine a G-d who “doesn’t think about things”). Judaism is filled with a vision of a world where all mankind will get to experience a world of G-dlinesss, peace and goodness. A world where mankind as a whole serves G-d. Perhaps you should read (again) the works of the Prophets (Isiah for a start), and see if that does not give you a picture of a G-d who has great aspirations for all peoples. I hope this is of some help, Blessings.