Google Cloud does not have first-party managed Kafka service. For messaging, you can mostly use Cloud Pub/Sub. If you need capabilities of Kafka, then you can run Kafka cluster either as a third-party managed service (e.g., from Confluent Cloud), or run it on Kubernetes with an operator.
If you want to run Confluent's Kafka platform yourself, you can use the Confluent Operator, which can provision Kafka clusters on Kubernetes Engine. See Confluent Platform on Google Kubernetes Engine documentation for more detail.