First, run the development server:

npm run dev
# or
yarn dev
# or
pnpm dev

Open https://localhost:3000 with your browser to see the result.

You can start editing the page by modifying app/page.tsx. The page auto-updates as you edit the file.

make a file name .env.local on root and input your own environment for this app.

NEXT_PUBLIC_CLERK_PUBLISHABLE_KEY=
CLERK_SECRET_KEY=
CLERK_WEBHOOK_SECRET=

NEXT_PUBLIC_CLERK_SIGN_IN_URL=/sign-in
NEXT_PUBLIC_CLERK_SIGN_UP_URL=/sign-up
NEXT_PUBLIC_CLERK_AFTER_SIGN_IN_URL=/chat
NEXT_PUBLIC_CLERK_AFTER_SIGN_UP_URL=/chat

NEXT_PUBLIC_STREAM_KEY=
STREAM_SECRET=

NEXT_PUBLIC_WEB_PUSH_PUBLIC_KEY=
WEB_PUSH_PRIVATE_KEY=

If you want to learn how to create it please follow below tutorial👇:
➡ Tutorial Link 💚: Next.js WhatsApp Web Clone (Stream, Clerk Auth, Web Push Notifications, Tailwind CSS, TypeScript)