total beginner, what do i need to get started?

I'm a huge fan of the claymation in jack stauber's video clips and short films, it's so cool and creepy! I've got a gift card of 25€ for a local hobby store, and am looking to buy some fimo clay. I was wondering if this is right (for a first project) and if i'd need any more tools. I can borrow the green screen from school, but i'm wondering about any modelling tools you all swear by? does a phone camera suffice for stopmotion? do you use a certain software for stopmotion? any help and advice is appreciated! thanks in advance!