Change icon

Hello,

Is it possible to change these icons : https://imgur.com/a/twqeT by an image who has the same size ?

I did not find the thread to answer my question. Can you give me the link ?

Here is the link from my page : http://www.micropole-learning-solutions.com.qual.micropole.com/index.php/portfolio-item/la-banque-postale/

Thank you