Seems like you have not started Zookeeper and Kafka services properly.
Execute the commands attached below in order.
Zookeeper:
./bin/zookeeper-server-start ./etc/kafka/zookeeper.properties &
Kafka start:
./bin/kafka-server-start ./etc/kafka/server.properties &
schema registery:
./bin/schema-registry-start ./etc/schema-registry/schema-registry.properties