upload

Hello, tell me how to properly load a file (any)? I turned to the manual and use 

PHP Code:

$this->request->getFile() 


but it did not help, kept getting data about the file "NULL"...

It's embarrassing to ask you, lead or link to a working example.

Specification:
I want to learn how to download a file (by specifying a location) and get some data about it, for example its size or type.

P.s
Thank you for understanding.