You must have the appropriate extensions installed on the server. The mention of how and where to install them should be in the description of the module you are installing.
If you don't have them, try searching online or write to the module's developer.
The installation of such things is done through the ssh console of the server, if you are dealing with this for the first time, it is better to entrust this procedure to someone with experience.
And judging from your question, I'm not sure you need this extension. Infoblocks has a built-in image optimizer, for previews and detail.
And for custom properties, you can use the Bitrix compression method: https://dev.1c-bitrix.ru/api_help/main/reference/c...
The last parameter is the quality of pictures.