For bedding, I suggest straw. Cheap, fluffy, and makes great mulch or compost after it’s all peed upon.
However, you do need to know one rule about goat bedding: Anything on the ground is bedding.
On the left you have straw (bedding) and on the right you have hay (food), but if they’re on the ground, it’s bedding. Same with leaves and branches. Goats are foragers, so stuff sticking UP is food, stuff laying DOWN is bedding. It’s infuriating to find your goat sleeping in her food, just cause some fell on the ground, but that’s the way it is. And the bedding needs to be changed frequently, depending on the sleeping space. If you have the bedding in a kennel, daily or every other day FOR SURE. Old tinkle is ICK. But if you have a larger space, you can change it less frequently. How do you know when it’s time? Just stir it around a bit every day or so. You’ll know.