I want to make sure this is the correct translation for “If I cannot move Heaven, I will raise Hell.” Flectere si nequeo superos, Acheronta noveno.
It does indeed roughly mean “If I cannot move heaven, I will raise hell.” More literally: If I cannot bend heaven to my will, make heaven do my bidding, etc., I will move, set into motion, rouse hell.
Note that for heaven and hell, Vergil did not use words which mean exactly that; he thought in different terms altogether. For “heaven,” you actually have superi, which are “those above” (i.e., the gods above). For “hell,” you have Acheron, which is a pretty harmless river in Greece, but in ancient mythology, this river was closely associated with the underworld (the realm of the dead), and for Vergil in particular, with Tartarus, a deep abyss and site of torment.