WordPress Site Repair with Backup Setup

I need a one-time fix for my WordPress site (savvywinesoirees.com) hosted on Bluehost.

The issues:
- Site down with a 500 Internal Server Error.
- Downloads PHP files instead of displaying pages.
- Divi theme/builder malfunctioning.

Requirements:
- Check and repair PHP settings (must be set to PHP 8.1 with PHP-FPM enabled).
- Reset .htaccess file to WordPress defaults.
- Confirm Divi theme is active and Divi Builder plugin is enabled.
- Clear any server-side cache.
- Pull error logs and inform me of the crash cause.
- Install and configure UpdraftPlus (free plugin) for automatic backups to Dropbox or Google Drive.

Important notes:
- This is a one-time job only.
- I am not looking for ongoing management, SEO packages, or monthly contracts.
- Please quote a fixed price for this one-off repair and backup setup.

Ideal Skills and Experience:
- WordPress troubleshooting expertise.
- Familiarity with Bluehost hosting.
- Experience with PHP and Divi theme.
- Backup plugin configuration knowledge.