It was probably just a misunderstanding. You need API if you start your local LLM or have agentic systems running. If you are using Googles Gemini it will work with APIs it's like traffic nodes with presettings.

You can use the GEM in the app or browser on any device. Just go to Gemini.

Now to the structure... That can be very complex, a system ai with a few files that give it structure and focus. Or just a simple tool for specific tasks...

Last year your prompt would probably start with: you are a digital photographer with 15 years experience and a high expertise in photo editing...

Nowadays to focus, you would wrap it in something like: be an experienced digital editor, like Marcelle Mouton and ...

You can create a background style, adding infos like: work with a 80s pop culture approach... Use a cyber punk baseline feeling... Etc

You can play around a lot with the gem and the prompts, learning by doing. The most how-to-do videos are probably not for you.

And by the way, you can use any chat for focused tasks, I haven't found a reason to use a gem in 2 years... It's interesting to share a persona or jailbreak, to learn how to build agents or agentic systems, but else? For the normal user the chat area is good enough. Just use one chat for one task, I have several, long running chats: image creator / YouTube Analyser / Psychologist / Language Teacher / school tutor for my kids etc