can we use kafka with nodejs without any external database?

I am new to kafka and I want to use it with Node JS. I want to query the username and password of user in Node JS without external database. As for as I know Kstream and Ktables don't work with node JS.

If possible, can someone create me a simple REST API for verifying username and password? I can produce and consume messages in kafka but the main problem is that I can't integrate kafka when sending a request with to API with Node JS.

If we can't use it without an external database with nodejs, then why use it?

This is what I have tried:

        import avro from "avsc";
        import { Kafka } from "kafkajs";
    
    const Type = avro.Type.forSchema({
        type: "record",
        fields: [
            { name: "Kind", type: { type: "enum", symbols: ["CAT", "DOG"] } },
            { name: "name", type: "string" }
        ]
    })
    
    const buff = Type.toBuffer({ Kind: "CAT", name: "Arslan" })
    const val = Type.fromBuffer(buff);
    console.log(buff)
    console.log(val)
    
    const kafka = new Kafka({
        clientId: 'Producer-Application',
        brokers: ['localhost:9092', 'localhost:9093', 'localhost:9094'],
    })
    const ProducerFun = async () => {
    
        const producer = kafka.producer();
        await producer.connect();
        const MessageValueEncoded = await Type.toBuffer({ Kind: "CAT", name: "Arslan" })
        await producer.send({
            topic: 'test-topic1',
            messages: [{
                value: MessageValueEncoded
            }]
        })
        await producer.disconnect()
    }
    
    const ConsumerFun = async () => {
        const consumer = kafka.consumer({ groupId: "test-group-2" });
        await consumer.connect();
        await consumer.subscribe({ topic: 'test-topic1', fromBeginning: true });
    
        await consumer.run({
            eachMessage: async ({ topic, partition, message }) => {
                const val = await Type.fromBuffer(message.value);
                console.log(val)
            }
        })
    
    }
    ProducerFun().then(() => {
        ConsumerFun()
    })