Recording a single person is super easy, especially as you are learning. You can get an inexpensive headphone/mic combo and use Audacity or Garage Band. When you add additional mics, things start to get more complicated. You can’t just run 2 or more USB mics into a single computer, as delays within the USB subsystem can cause the audio to be out of sync. In this case, you will need to use some sort of mixer to handle the multiple inputs and output a single stream to your device of choice.
So, consider your first podcast a learning experience, and don’t worry too much about being perfect right away. You should get a TASCAM DR-40 and a set of headphones. It has good built-in mics and is a great little device that will last for a long time. You can also add better mics as you grow. Use a camera tripod to mount it, and start talking. It records to a flash card and can also be used as an external flash drive. The whole setup should cost less than $200. Just focus on improving and having fun.