Warning

Warning: require(C:\xampp\htdocs\CodeIgniter4\../app/Config/Paths.php): Failed to open stream: No such file or directory in C:\xampp\htdocs\CodeIgniter4\index.php on line 34

Fatal error: Uncaught Error: Failed opening required 'C:\xampp\htdocs\CodeIgniter4\../app/Config/Paths.php' (include_path='C:\xampp\php\PEAR') in C:\xampp\htdocs\CodeIgniter4\index.php:34 Stack trace: #0 {main} thrown in C:\xampp\htdocs\CodeIgniter4\index.php on line 34

A little more information would help. 
Which PHP version?
Which CI version?
content of .htaccess if present...

Your folder structure is wrong.
See https://codeigniter4.github.io/CodeIgnit...ith-apache

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