进入目录：ChatGPT-Next-Web/app/config/server.ts，找到如下代码，添加这三行即可

export const getServerSideConfig = () => {
  if (typeof process === "undefined") {
    throw Error(
      "[Server Config] you are importing a nodejs-only module outside of nodejs",
    );
  }

//添加以下两行
const apiKeys = (process.env.OPENAI_API_KEY ?? '').split(',')
const apiKey = apiKeys.at(Math.floor(Math.random() *apiKeys.length)) ?? ''
  
  return {
    apiKey,  
    code: process.env.CODE,
    codes: ACCESS_CODES,
    needCode: ACCESS_CODES.size > 0,
    baseUrl: process.env.BASE_URL,
    proxyUrl: process.env.PROXY_URL,
    isVercel: !!process.env.VERCEL,
    hideUserApiKey: !!process.env.HIDE_USER_API_KEY,
    enableGPT4: !process.env.DISABLE_GPT4,
  };

如果是用Vercel部署，则在Vercel上修改环境变量OPENAI_API_KEY，key与key之间用逗号隔开即可，然后重新redeploy