Do I need to additionally include the library after installation?

Question

PHP

After installing Composer and the Guzzle dependency, the test request is not sent using Guzzle. Before that, I worked with JS and there it was necessary to connect libraries using import, is it necessary to do something similar in the case of php?

Answer 1

From documentation.
After installing, you need to require Composer's autoloader: That is, after installing, you need to enable Composer's autoloader. After that, the libraries installed by the composer will be connected automatically (provided that namespaces are used correctly)
require 'vendor/autoload.php';