Program Help Please....

ok so im trying to run the simple hello world! In kali linux, but when I try to open it, it say that the program is a directory heres a few picture so i can know what i am doing wrong......

Theres the file so you can see it on my desktop a.out

now this is the file thats inside the main.c

ok now heres my top of the line programing

ok and now when I try to open it I get this......oh by the way I cd / Desktop but for some reason my Kali linux doesn't show Desktop, but its in Desktop cause when i save things it pops up in Desktop any picture

any type of help will help thanks for taking your time in looking at this