How to make a continuous picture that moves to the left like a moving background?

Question

CMS

Hello, help me solve the problem, I'm making a site on wp, the template has such a block with a moving background to the left, I searched the entire Internet in search of another picture, how to make it like that? To make it look continuous while moving? This is how it was, but I would insert a city or a neutral light background there, cut it to the right size, paste it, and it looks like pieces, and not merged like this