need to use CocoaPods, Ruby, and Xcode to set up a development environment.
trying to install CocoaPods and running into compatibility issues with Ruby versions (>= 2.7.0) and can't use rbenv.
can't install cocoaPods
We can't help you because you've given us the bare minimum of information.
This is like saying, "A bit of my car is broken", but not telling us what bit is broken.
What macOS version are you on? How are you installing CocoaPods, etc.?