Website is broken, 500 server error, i don't know what's wrong

I am having problems with an existing site. So this really isn’t an install issue, but I’m getting a 500 error. In my logs I have found this information. I believe I have all of the files loaded it mentions. Can anyone please help me figure out what is missing so I can get my site back up?

[12-Sep-2021 12:48:23 America/Boise] PHP Warning: include(/home1/brandio1/public_html/lyndaschlosberg/application/bootstrap/autoload.php): failed to open stream: No such file or directory in /home1/brandio1/public_html/lyndaschlosberg/concrete/bootstrap/autoload.php on line 8
[12-Sep-2021 12:48:23 America/Boise] PHP Warning: include(/home1/brandio1/public_html/lyndaschlosberg/application/bootstrap/autoload.php): failed to open stream: No such file or directory in /home1/brandio1/public_html/lyndaschlosberg/concrete/bootstrap/autoload.php on line 8
[12-Sep-2021 12:48:23 America/Boise] PHP Warning: include(): Failed opening ‘/home1/brandio1/public_html/lyndaschlosberg/application/bootstrap/autoload.php’ for inclusion (include_path=’/home1/brandio1/public_html/lyndaschlosberg/concrete/vendor:.:/opt/cpanel/ea-php73/root/usr/share/pear’) in /home1/brandio1/public_html/lyndaschlosberg/concrete/bootstrap/autoload.php on line 8

[12-Sep-2021 12:48:23 America/Boise] PHP Fatal error: Cannot use Concrete\Core\Foundation\Object as Object because ‘Object’ is a special class name in /home1/brandio1/public_html/lyndaschlosberg/concrete/src/Foundation/ClassLoader.php on line 5

There’s two different problems here.

The one about ‘Object’, is because it must be an older version of concrete5, but your hosting is running it on version 7 of PHP. The fix for this is to set the PHP version to 5.6, through your hosting control panel (or by asking your host).

The one about it failing to load autoload.php is a bit more unusual, that seems like you have some core files missing. But it might be something triggered by the Object issue. So I’d aim to get your site running on PHP5.6 and see how you go.