Reply to New to the scene!

So hey everyone I'm new to the DJing scene! I just ordered a Numark Mixtrack and can't wait for it to arrive. Anyways, I will be only a bedroom DJ using a desktop for almost 100% of my play. Anyways I really don't have the $$$ to buy a DJ IO or anything at the moment so I'm wondering what not having it will prevent me from doing. I basically just want to listen through my headphones, or through my monitor speakers, am I able to do this. Also, if I buy like a 10$ USB soundcard what will that help with?

Thanks and hope to hear back from you guys soon!!!!!