Best way to modify screens that will fit on 800x600 resolution screen

I have a perspective project which I have created using a resolution that is bigger than the screen resolution it will be running on. Even though I am using perspective this project will not be shown on any other device with a different resolution. What is the best way to modify my project to insure that it will fit on the smaller resolution? Would it be shrinking my existing screens to the smaller size of 800 by 600 and then making sure everything fits within that view within the designer?

What containers are you using for your existing screens?

Main containers are flex but I do have coordinate containers within those flex containers. Probably not the best idea but thats what i have. I'd definitely have to change the coordinate container sizes to make it work.

Coordinate containers(in percent mode) have an option to set a fixed aspect ratio. That combined with the flex might be able to scale reasonably nicely.

Unfortunately, trying to fix scaling in perspective after the fact isn't the easiest process. I try to design it in as much as I can at the early stages or try and design it for the most common resolution at the very least.