the game is incredibly easy to solo if youre geared. if not then you might have a tough time especially in higher level dungeons (dont expect to solo 8 man dungeons even with the bestest best best gear lol)
at low levels its best to party (at your level you can do spooky lvl 30) just because its faster. however you dont really need to, itll just take that much longer lol
as for parties, cant help you lol i almost never partied with random ppl and
afaik things are kinda dead xD but uh the best solution is to find an active guild and ask guildmates to grind and such