Hi fedi, I need advice

I want to make live Linux .iso
Preinstall some of my most used software into it
Sometimes update it, so it must not be too hard
Give it some persistence storage, so I can tune it without rebaking system .iso

And put all that on Ventoy-powered USB

Is it even possible? What are the best tools for that? Where do I even start?

(I tried just mounting USB drive from live iso but it failed, I assume it's due to ventoy magic)