Your English is fine, and thank you. In the ACP (Admin control Panel) in debug mode (you must be in debug mode), you can create a new ACP "options" setting. If you do not know how to do this, I will try to find you a tutorial. It should be easy enough to search for one.
Create a new setting in ACP options: "acp_imagepath". It will be automatically appended to "$vBulletin->options", you will then be able to access this "acp_imagepath" variable in all your templates.
In your templates:
Code:
{vb:raw vboptions.acp_imagepath}/ <!-- rest of your path or image -->
In summary: "vboptions" is available to all templates and is already pre-registered, whether it should be is another question.
This is only one method of many. It was chosen because it best fits your criteria.