[ubuntu] plz help installing NAS on ubuntu desktop 16.04

i dont know from where to start, i installed ubuntu desktop 16.04, after readings , i found out i have to install samba which i did , but non of the posts i rade was useful to configer samba , even when i restart the system , the exteal hard disk i had it shared was not shared any more ,
some other people says i have to install ubuntu server, i prefere to use desktop and i am planing to create small nas drive to use it with ip cameras as net work storage
my question is
1- where to start?
2- any good guide in details?
3- i wish u guys fellow up and i will be able to update here my problems
4- samba configration good guide, since every one uses different methods ,like system-config-samba which never worked with me , and edit samba with nano also didnt work fine,
most important question, they create the share 1st then assign space , while i have an exteal hard disk which i want to share it as nas smb or cfs any help