Troubleshooting WordPress MySQL Extension Error

I need assistance with troubleshooting an issue on my WordPress site. The error message reads, "Your PHP Installation Appears to Be Missing the MySQL Extension Which Is Required by WordPress.” This issue arose right after I recently updated my PHP version and I updated the php version because it was showing some error regarding that.

Ideal Skills and Experience:
- Strong expertise in PHP and WordPress
- Experience troubleshooting WordPress errors
- Knowledge of MySQL and PHP extensions
- Ability to provide clear, understandable explanations