CMS and grids and lightboxes

Design help General
1

I am doing something wrong.

(1) How can I make a CMS;
(2) how stretching the images across the grid very playful (masonry grid) or making all the images a lightbox?

https://preview.webflow.com/preview/234-11709c-9354287f83ed1c-841ec8b590c89?utm_medium=preview_link&utm_source=designer&utm_content=234-11709c-9354287f83ed1c-841ec8b590c89&preview=b6073b6950c42bffd0a7d1f70d1eb502&pageId=5e00b14adcc8ad4953724174&itemId=5e00b14adcc8ad9a977241a6&mode=preview