In cases where a hearing loss distorts incoming sounds, a hearing aid can do nothing. All deaf people can read lips. Some deaf people are very skilled lipreaders, but many are not. This is because many speech sounds have identical mouth movements. For example, b and p look exactly alike on the lips.
All deaf people use sign language.
Many deaf people, especially perlingually deaf people, use sign language. Many others do not. In addition, there are several kinds of sign language systems. Deaf people are not sensitive to noise. Some types of hearing loss actually accentuate sensitivity to noise.