Flyff Modeling help

[EienNoAi]

Hello guys, I need help, I downloaded and prepared files for flyff, I tried it on test, works, now I need to start with the modeling, can anyone tell me what do I do? What do I use, is there some free program to use it? and if so how do I even do it? I'm totally new in this and any help will be of use, thank you <3