Create a variable on UI as a list of variables

I have a configuration with a bunch of variables and I need set up all variables on UI before running a pipeline.
It always takes time and you need to be precise with the name of the variable and so easy to make mistakes.
How to just create 1 (one) variable and use it as a list of variables for the build.
How to expand that variable in the list of variables when running a pipeline?
What is the best way to do it?