Each item has care instructions in the description.
Generally speaking, items made with acrylic, bamboo, and cotton materials can be machine washed.
Superwash wool can also be machine washed, but it’s recommended to do it on a lower setting without many other garments to agitate it.
With any hand knit item, when in doubt, hand wash it with a gentle detergent or wool wash and lay it flat to dry is always the best default. You can also use a hair dryer on low to help dry a hand washed item.