Upgrading from Drupal 9 to Drupal 10 involves several steps, and it's important to plan and test the upgrade process thoroughly before implementing it on a live site. Here's a general overview of the process:

1. Back up your Drupal 9 site: Before upgrading, it's important to create a full backup of your Drupal 9 site, including the database, files, and configuration. This will allow you to restore the site if something goes wrong during the upgrade process.

2. Check compatibility: Review the list of contributed modules and themes that are compatible with Drupal 10 and remove any that are not.

3. Update core and contrib modules: Update the core Drupal 9 installation and all contributed modules to their latest versions compatible with Drupal 9.

4. Upgrade to Drupal 9.1: Upgrade your site to the latest version of Drupal 9.1. This is an important step as Drupal 9.1 includes important security and compatibility improvements for the upgrade to Drupal 10.

5. Test your site: Test your site thoroughly to ensure that all features and functionality are working as expected.

6. Upgrade to Drupal 10: Use the update.php script to upgrade to Drupal 10.

7. Check for deprecated code: Review your custom code and check for any deprecated code. Drupal 10 removed some APIs that were used in Drupal 9, so you may need to update your custom code to use the new APIs.

8. Test your site again: Test your site again to ensure that all features and functionality are working as expected.

9. Deploy to a live site: Once you have successfully tested your site, you can deploy the upgraded Drupal 10 site to a live environment.

Please note that this is a general overview, and the specific steps and details may vary depending on your specific site and configuration. It is highly recommended to consult the official Drupal documentation, and seek professional help if you are not comfortable performing the upgrade.