(This article is translated from https://zenn.dev/hikaelis/articles/b93cc6f94a6bd3)
This shows how to access to GPT4/3.5 using openai v4 of JavaScript Library.
The usage was changed from version 4 . I tried it on node18.

1. Install the Library

Install openai v4 via npm or yarn

npm install --save openai
# or
yarn add openai

2. Get API KEY of OpenAI

Get API KEY of OpenAI from OpenAI site. Please be careful it isn't the same as ChatGPT Plus.
https://openai.com/blog/openai-api

3. Coding

The usage was significantly changed from v4 (it became easier)
I learned from this video(is it ok? cuz he showed his API KEY...)
How to use the OpenAI API in NodeJS

The example of coding is below↓

const openai = new OpenAI({
    apiKey: OPENAI_API_KEY // API KEY
})
const message = "message to GPT"
const completion = await openai.chat.completions.create({
                model: "gpt-4", // GPT Model name
                messages: [{ "role": "user", "content": message }],
});
console.log(completion.choices[0].message.content); // GPT answer

You can confirm available GPT models on this Document.
https://platform.openai.com/docs/models

4. Summary

If you just want to listen to GPT in chat format, I think this usage is sufficient.
I am actually using this usage to run the bot. (I will write an article about it later.)
https://github.com/hikaelis/nostr_shinjiro_bot_public

GPT is rapidly making progress, so usage will probably be changed when updates. So please check out openai-node documents.
https://github.com/openai/openai-node