Missing 'vendor/autoload.php'

[AungZinPhyoOo]

Warning: require(D:_Xampp\htdocs\mike42\example/../vendor/autoload.php): Failed to open stream: No such file or directory in D:_Xampp\htdocs\mike42\example\barcode.php on line 2

Fatal error: Uncaught Error: Failed opening required 'D:_Xampp\htdocs\mike42\example/../vendor/autoload.php' (include_path='D:_Xampp\php\PEAR') in D:_Xampp\htdocs\mike42\example\barcode.php:2 Stack trace: #0 {main} thrown in D:_Xampp\htdocs\mike42\example\barcode.php on line 2

Firstly, I downloaded zip file from github. But I got above error.
please give me video record or sample documentation for beginner level.

[parallels999]

composer require mike42/escpos-php