Bitcoin is often described as anonymous because it is possible to send and receive bitcoins without providing any personally identifying information. Bitcoin is designed to allow its users to send and receive payments with an acceptable level of privacy, as well as any other form of money. However, Bitcoin is not anonymous and cannot offer the same level of privacy as cash. As Gordon said, regardless of how anonymous or pseudo-anonymous bitcoin is, services that transfer bitcoins to dollars are not anonymous and therefore making transactions would not be anonymous in any meaningful sense.
For anyone to make a transaction on the Bitcoin blockchain, you need a wallet that is connected to a Bitcoin node.