"after I press Run."
This doesn't sound like you are using the CS50 IDE (http://cs50.io). Or, if you are, you may not have created it using the CS50 template. If you think that's the case, here are instructions
apropos is a commad to search for the appropiate command, for example apropos network will give you a list of commands related to that topic
Other commands of interest are man, which and whereis
Always read the man page of any command to know more about it.
Some of the "Shorts" in Week 0 and Week 1 dip a little into this (not much!) but they do provide a little insight into where you can go and do further research to find out the answers you may be looking for. Particularly, you can view the manual pages for whatever you are looking for in c. For example if you want to see the man page for the function printf, ...