Is there a program that would take pictures smaller than 700px and create an 800px canvas and center them and save?

Question

Adobe Photoshop

let's say I have 100 photos with a resolution of less than 700x700px, I need to stretch them without losing quality - that is, just create an empty canvas, for example, at 800x800 and put them in the middle of it. Is there such a program? If not, what is the easiest way to write? C# or nodeJS (if you can just do it) - it would also be convenient if the Web format would be converted to the same JPG for example. If no such tool exists. then tell me what will be the easiest to write on