Good question.

I started with the art myself, trying to come with layer combinaisons that always look great together. For the code I initially envisioned adding elements to a canvas according to a JSON file but doing it in Photoshop allowed more control art-wise.

I believe in many Adobe software you can simply import a js file as a script.

You can then start the file with the following lines to access the Photoshop DOM. The first line is a small dependency I found online for JSON compatibility. Another thing to note is that it's ES5 Javascript so no arrow functions, let variables, includes methods, etc...

You have lots of ressources online for that but feel free to ask if you have any question.

I took the classes of Andrei Neagoie to learn how to code. I saw he just released an NFT creation special. He always has great courses but it's a monthly membership.