First things first, sign up or log in to Supabase and create a new project. Jot down the project URL and the API keys. You'll need these for adding authentication features, like password reset.

Before you can enable password reset, you need to set up an SMTP server to send emails from Supabase. In the Supabase dashboard:

• Head over to Authentication -> SMTP Settings.
• Fill in your SMTP server details:
• SMTP Host
• SMTP Port
• Email (From Address)
• Password
• Default URL (optional), usually your frontend base URL where users will get the reset email.
• Save those settings.

Go to Authentication -> Settings and scroll down to the Email Auth section.

• Make sure Enable email confirmations is checked.
• Save the settings if you made any changes.

In your frontend app, create a form where users can enter their email to request a password reset.

• Use the Supabase client library to handle the password reset request. Here's a sample code snippet for requesting a password reset:

import { createClient } from '@supabase/supabase-js'

const supabaseUrl = 'https://your-supabase-url'
const supabaseKey = 'your-anon-key'
const supabase = createClient(supabaseUrl, supabaseKey)

// Function to request password reset
async function requestPasswordReset(email) {
  const { error } = await supabase.auth.api.resetPasswordForEmail(email)
  if (error) {
    console.error('Error requesting password reset:', error.message)
  } else {
    console.log('Password reset email sent successfully!')
  }
}

The user will get an email with a link to reset their password. This link should take them to your app where they can set a new password.

• In your frontend route handling password resets, grab the access_token query parameter and set the new password using Supabase's API. Here's an example code for setting a new password:

import { createClient } from '@supabase/supabase-js'

const supabaseUrl = 'https://your-supabase-url'
const supabaseKey = 'your-anon-key'
const supabase = createClient(supabaseUrl, supabaseKey)

// Function to update the password
async function updatePassword(accessToken, newPassword) {
  const { error } = await supabase.auth.api.updateUser(accessToken, { password: newPassword })
  if (error) {
    console.error('Error updating password:', error.message)
  } else {
    console.log('Password updated successfully!')
  }
}

Now, let's test the whole process:

1. Submit an email for password reset from the form you made in Step 4.
2. Check the email, click the reset link, and follow it to the password reset page.
3. Set a new password using the function from Step 5.
4. Verify that the password has been updated and that you can log in with the new password.

Double-check that the SMTP server settings are correct and that the emails are delivered without ending up in spam folders.