There are a few steps you can take to try to fix the “critical error” on your WordPress website:

Learn more about debugging in WordPress
- Check for updates: Make sure that your WordPress installation, as well as any plugins and themes you’re using, are up to date.
- Check for compatibility: Make sure that the versions of WordPress, your theme, and your plugins are all compatible with each other.
- Deactivate plugins: Try deactivating all of your plugins to see if the error goes away. If it does, reactivate your plugins one by one to determine which one is causing the issue.
- Switch to a default theme: Try switching to a default WordPress theme, such as Twenty Twenty, to see if the error is caused by your current theme.
- Check your error logs: Look at your website’s error logs to see if they contain any clues about what might be causing the issue.
- Contact your hosting provider: Contact your hosting provider and ask them if they have any logs or information that might help you troubleshoot the issue.
- Look into the error message: The error message should give you more details on what went wrong and help you to understand the root cause.
If none of these steps resolve the issue, it may be necessary to seek help from a WordPress developer or a professional website maintenance service.