wondering how to work with multiple files at once

Hello, I am very new to using python, and I have two files with the file extension '.py'. I want to be able to run the one, which is my total project, entitled program.py, while also running another file called test.py. The reason I want to do this is so that if there's a block of code I want to just test really quick, I can c/p it over to the test window and run it. The problem is that I can't seem to do this, because when I try to open both files, pycharm only seems to recognize the first file as the project, and it considers the second file an outside resource, not a part of the project.

I hope I've been detailed enough, please let me know if I haven't.

Can somebody tell me how to accomplish this?