Live Javascript execution in editor

I'm trying to create a live JavaScript executor or real time prototyping app for the script editor on the web. I have searched a lot but not getting any pointer on how to get started. An example of what I am trying to do is https://quokkajs.com/ but a lot simpler in terms of scope.

Basically the idea is not to use log statement instead I should be able to see array, variables and other expression values on the real time.

Any helpful resources or pointer in this regard will be highly appreciated.

Regards, Sharjeel