Alright, let's get started with setting up your environment for using Supabase with Puppeteer for web scraping. First things first, you need a JavaScript environment with Node.js.

Here's how you can set up Node:

• Head over to the official Node.js website and grab the recommended version for your operating system.

• Follow the installation instructions. Once it's installed, open your terminal and type node -v to check if Node is properly set up. You should see the version number pop up.

• You'll also need npm (Node Package Manager) to install JavaScript packages.

With your environment ready, it's time to install Puppeteer. Puppeteer is a Node.js library that gives you a high-level API to control Chrome or Chromium via the DevTools Protocol.

To install Puppeteer, just open your terminal and run:

npm install puppeteer

Next up, let's create a project in Supabase, which is an open-source alternative to Firebase.

• Go to the Supabase website and click on "Start your project".

• Sign in with GitHub. Once you're in, you can create a new project.

• Give your project a name, set a database password, and click "New Project".

Now, let's get our hands dirty with Puppeteer to scrape websites. Here's what you need to do:

• Create a .js file in your local environment.
• In this file, require puppeteer by adding: const puppeteer = require('puppeteer').

Next, create a function that launches a browser and opens a new page on your chosen website.

const puppeteer = require('puppeteer');

async function scrapeWebsite() {
  const browser = await puppeteer.launch();
  const page = await browser.newPage();
  await page.goto('https://yourwebsite.com');
  
  // Insert more code for extraction here.
  
  await browser.close();
}

scrapeWebsite();

Finally, let's save the scraped data into your Supabase database.

First, install the Supabase JavaScript library by running npm install @supabase/supabase-js in your terminal.

Then, import this package into your JavaScript code (at the top of your .js file) and establish a connection to your Supabase project:

const { createClient } = require('@supabase/supabase-js')

const supabaseUrl = 'https://xyzcompany.supabase.co'
const supabaseKey = 'public-anon-key'
const supabase = createClient(supabaseUrl, supabaseKey)

With this connection, you're all set to save data to your Supabase project. Let's say you have an array of objects named scrapedData.

To save this data to Supabase, use the .from() and .insert() methods from the Supabase client:

const { data, error } = await supabase
  .from('my-table')
  .insert(scrapedData)

Don't forget to replace 'my-table' with the name of the table where you want to store the data in your Supabase project. Make sure your table structure matches the structure of objects in your scrapedData array.

And there you have it! That's how you can use Supabase with Puppeteer for web scraping.