Fan stop spinning...

so what you are saying is it might be a problem with my power cord or
the fan. I had major dust on the fan when i looked and that was the
first thing i thought it might be so i cleaned all the dust, but it
still didn't work. How would i test to see if its the power cord? And
if it is the fan how can i replace it on my own to save money of
getting someone else to do it. Thank you for your help!