removing link from image

hello all,

i’m pretty new to WP and i’m trying to remove a link from an image (gallery)

the theme i’m using is tetris

https://wpexplorer-demos.com/tetris/

somehow i was able to remove the text/white box below so the theme would look more like a portfolio theme but i’m still having a hard time removing the link from images.

https://evanstonmarketing.com/

i would truly appreciate your help