Got into game for guilty gear

Hi I just got into this game after seeing the guilty gear Collab and I was wondering how easy or hard would it be to get all the GG characters as a new f2p player?

I'm actually invested in the story and I'm gonna keep playing the game after but right now I'm focused on getting the GG characters and it seems like it's gonna be rough.

Are there any tips for getting more pulls? Especially for Jack-O'.