Asking for help regarding using a buffer tool

[JeeYoungKim]

Hello, I am Jee from Korea. I am a beginner in learning ArcGIS. I've been learning ArcGIS for the last two weeks from a course called Fundamentals of GIS provided by Coursera. I am writing to ask for help regarding using buffer tool. I am using ArcMap 10.8.2 and this is part of an assignment to pass this course. I attached the ArcMap file and PDF file (page 29 and 30) for your convenience. The problem is that the buffer tool does not work at all. I did exactly what the instruction (page 30) says but nothing has changed.

When I try to close the ArcMap programme, the warning message pops up saying that the map document has executing or pending geoprocessing operations. I attached the message below. I wonder if the RAM capacity of my notebook, which is 4GB, might have caused these problems. 

Is there anyone who would help me with this? Thank you so much!

[MichaelPirker]

Couldn't open your files man

[JeeYoungKim]

Hi, thanks for your reply. I uploaded my files again. Hope you can open them this time!

[MichaelVolz]

How long did you wait after starting buffer tool before closing ArcMap?

Do you know if background geoprocessing is enabled on that machine?

Do you have access to another computer with more RAM to try this operation on?

[JeeYoungKim]

Hi, many thanks for your reply. I waited for hours before closing ArcMap. I've tried a lot of times, but nothing has changed. Could you explain how to check if background geoprocessing is enabled on my notebook? Unfortunately this is the best notebook that I can find in my house. Do you think my 4GB RAM affected this situation?  Thanks!