Hi. I think I read somewhere that non-paid enterprise or individual developers don’t get any additional projects unlocked. Unfortunately, I can’t find the exact source right now. But basically, you can just use the demo project. You can easily change the project name.
If you need more API calls or additional projects, you’ll have to get in touch with Aqara here: https://developer.aqara.com/contact
If you want to know more about the API limits, you can check out this thread:
Edit: I found it! It’s hidden in the developer portal at the top right under the 【Important Notice】Release Notes View now notice. It says right there: For non-paying corporate/individual developers,only the default project is supported.