Only buy bows , and use arrows lvl 1 / 2gil . The hit rate is lower but you'll find your way later . Buy arrows higher lvl for difficult leves or NMs . I spent a stack of arrows 150k on a NM and the higher arrows lvl 47 are 250k a stack WTF !!! So , manage your gils , doing leves give a lot of gils , if you don't craft , sell all drop . Million is very easy to get .
Good luck and welcome .