
The missing the MySQL extension message means PHP cannot find the function mysqli_connect, so WordPress stopped before it touched your database. Check the PHP version and the extension list for the account, choose one MySQL driver set, and reload. Plugins, themes and wp-config.php are not the cause.
Your site is set to log errors to a potentially public file means two settings in wp-config.php, WP_DEBUG and WP_DEBUG_LOG, are both on while error display is off. Site Health never checked whether the log can be downloaded. The grade depends only on whether the log’s path sits inside your WordPress folder, so moving the file lowers the warning to recommended but never clears it. Read what you need, turn WP_DEBUG off, then delete the old debug.log, because turning logging off does not remove the file.

A scheduled event has failed does not mean the event it names tried to run and failed. Site Health compared each waiting event’s due time with the clock and found one more than five minutes overdue, or more than an hour if DISABLE_WP_CRON is set. The event it names is the oldest one still waiting, and often not the one that broke. Reload once after a minute, then find out why nothing ran wp-cron.php in time: visits answered entirely from cache, a broken loopback, WP-Cron disabled with no server cron, or a run that died partway.
