To clarify my comments (since comments don’t lend themselves to code blocks), you should only be using the .htaccess rules that apply to your particular WordPress installation. I’m assuming in this answer that you’re using WordPress greater than 3.5 (the current release as I write this is 6.7), and your question shows Subdomain Multisite. Thus, … Read more
Facing 503 error on PHP files after deleting hidden files from the root folder
Unable to embed Webmail Login page
Permissions is not the reason of 500 status. As answered here, you should try disabling plugins and themes. Examine error log to see what is true reason.
Internal server error when enabling Multisite in WordPress
Internal Server Error when echoing an OBJECT from wp ajax action function in functions.php to JS file
Can php warnings cause an Internal Server Error?
The message displayed by Chrome in your screen shot indicates the problem is more likely a network / server issue than a problem with the website. The puzzling part is you say you can open other sites on localhost. Do you access those sites the same way i.e localhost/someotherdir? What happens if you type http://127.0.0.1/2016/nuggetcity? … Read more
To upload a local WP installation to a server: Step 1 If you are on a host where you can expand an archived file (ie. Cpanel / File Manager) then easiest way is to ZIP or GZIP your entire WP install and upload it to the server, and use File Manager to expand the files … Read more
I strongly recommend you to change the PHP version from 5.6 to 7.3 (or 7.4). Also, check your htaccess file because broken .htaccess files might cause that issue. If the issue still persists, then check “error.log” file in order to see what the problem is.