I know it's possible to create a pop out window with html and know how about doing that, but could it be possible to do that with making some sort of plugin?
Bobby, unfortunately you do not provide enough details to give you a particular answer. Any way, it's possible to implement most of required functionalities via plugin development. Please take a look at this link to get more information about plugin development: https://docs.oxwall.org/dev:crash-course.