https://docs.typo3.org/m/typo3/docs-how-to-document/main/en-us/GeneralConventions/FileStructure.html#includes-rst-txt

Installation 

Target group: Administrators

Install yellowpages2 like any other TYPO3 extension.

Installation using Composer 

composer require jweiland/yellowpages2
Copied!

Installation using Extension Manager 

If you cannot use Composer, install yellowpages2 through the Extension Manager instead:

  1. Open the Extension Manager
  2. Switch to Get Extensions
  3. Search for yellowpages2
  4. Install the extension

Next step 

Configure the extension.