New to Java

ok i'm a total java noob...noob everything actually not just java but c++ and even macro progams. i've flirted with some macro programs although i can't write them. just looked at a few from an app called actools and understood enough of the command lines to repair or add/subtract values from it. that's it. now a game i play online has an application that someone wrote some yrs to keep track of things within the game. it's old, it needs to be updated/upgraded and needs new features added to it. how complicated is that to do?? i was to have a neighbour's daughter work on it but unfortunately she's had to return to school a month early. so i'm stuck with this thing and unsure how/what to do with it lol. if it's going to be complicated i'd rather not bother right at this moment. mmmmm help?