You mean the little icons next to the "Full Name", "age", etc?

Those use fontawesome icons, you can find the complete list of icons here. If you look at the pink square I drew below you will see fas fa-signature, replace the word signature with any other icon name, and then if you want to change the label that appears when you hover over the icon then change the description in the blue box I drew (make sure its within the quotations).

Be careful with icons that use 2 words for their name. For example, for gender I used the venus-mars icon, if you want to change that icon make sure you change the entire name _{(I have made that mistake too many times)}