JSON schema for SharePoint Site Script

I was using site scripts and site design to create site column and content type. I am facing two issues and I did not found their schema on Microsoft documentation those are below.

1. How to create choice, currency and lookup column. In relation to choice column other than fieldType how to give choices and default values?

2. While creating custom list, How to set newly created content type as a default content type in JSON. Please help me or you can send me relevant link.

Thank you in Advance,

Vishal Dhole