Need help in fetching a value from the list detail Page and storing into a global variable

Hey guys,

Below is my ask any help will be great.

Use Case 1: When my list details page is loaded it should capture a field value in the global variable.

Use Case 2: I have a list block, where we have different people. Beside those folks, we have a button called select, when that button is clicked it should capture the name of that person.

Why i want to do this–> I need to use the same variable to populate the a field in the airtable.