Road Bike Shoes What Else Do I Need Besides Road Bike Shoes? Pedals, Cleats?

What else do I need besides road bike shoes? Pedals, cleats? - road bike shoes

I am training for my first tri. I bought a used Trek 400 (good? Anyone? Who?) On eBay. Thus now been sent. I know I need walking shoes, but what else? I assume that not all cycling shoes are fought with all the pedals. Can you tell me what I need? I have the bike and that's all. Thank you!