Lets try to follow this : https://kafka.apache.org/32/documentation/streams/
First get the hello world working on local
Next get the payload representation in protobuff : https://www.tutorialspoint.com/protobuf/protobuf_integration_with_kafka.htm
Last try to get integrated with spark
https://sparkbyexamples.com/spark/spark-hello-world-example-in-intellij/