As @Val has already answered the question above just posting the code new users who wants to disable the SSL.
# --------------------------------------------------------------------------------
# Enable security features
xpack.security.enabled: false
xpack.security.enrollment.enabled: false
# Enable encryption for HTTP API client connections, such as Kibana, Logstash, and Agents
xpack.security.http.ssl:
enabled: false
keystore.path: certs/http.p12
# Enable encryption and mutual authentication between cluster nodes
xpack.security.transport.ssl:
enabled: false
verification_mode: certificate
keystore.path: certs/transport.p12
truststore.path: certs/transport.p12
# Create a new cluster with the current node only
# Additional nodes can still join the cluster later