What is the command to open a file located in etc in ubuntu 14/10?

Question

Server equipment

I have never worked with servers, I need to edit a file in mongodb at /etc/mongodb.conf
and a regular
CD etc gives an error I am now in /home/azureuser
how to go down to etc and then what command to open the file inside the console for editing

Answer 1

Run Midnight Commander:
mcedit /etc/mongodb.conf
Or nano:
nano /etc/mongodb.conf
Or vi:
vi /etc/mongodb.conf
Here's a book for you