How do I record a cash purchase from my vendor and track the inventory

How do I record a cash purchase from my vendor and track the inventory

Hi there,

I am a complete beginner and have no experience in accounting. Just trying to learn things as I go. I buy my stocks on cash basis only and I've never had an inventory system.

What I'm trying to do now, is to find a way to record stock purchases that I make which happen to be on cash terms. I don't send out a PO to my vendor as I buy directly from their store and as such, I'm not sure that raising a PO to record my inventory would be the way go. There's also the Bill option which I'm considering but would this be the right choice?

Any help will be greatly appreciated.