Dear Sir,
I would be happy to assist you in resolving the issues on your WordPress website that occurred after upgrading from PHP 5 to 7.4. Based on the error messages you provided, it seems that some plugins are not compatible with the new PHP version, and there may be an issue with the WP_POST_REVISIONS constant.
To fix this issue, I propose the following steps:
Take a full backup of your website and database, including all files and folders.
Deactivate all plugins and switch to a default WordPress theme such as Twenty Twenty-One.
Test your website to see if the issues are resolved. If they are, reactivate each plugin one-by-one, and test the website after each activation to identify the culprit.
If the problem persists, we will check your theme and look for any outdated code that needs to be updated.
Once we have identified the issues, we can proceed with the necessary fixes, including updating any outdated plugins or theme files. We can also ensure that your website is fully compatible with the latest version of PHP 7.4.
My bid for this project is $30 and I estimate it will take me approximately 12 hours to complete. I am available to start immediately and will work until the issues are resolved to your satisfaction.
Please let me know if you have any questions or concerns. I look forward to working with you.
Best regards,
Shahadat