Have taken a sample employee form to illustrate the multi tasking without blocking the UI.
When we run the application, initially the employee details needs to be saved. And then on entering the employee ID and by clicking on get button, in the background the getting of information for each data point is kept as a task. And we can observe that we can still save the details while getting the info. This indicates the UI is not blocked and its responsive.
Please note the below points: Included the comments whereever required. Did not spent more time on refactoring and kept basic validations only because the main task is illustrating the multi tasking. Had written a sample unit test case as well that is passed. Did not concentrated on more test cases as more refactoring of code is not written considering the main requirement.