[mothered]

as a newbie in this filed,

Im probably starting from networking (tcp/ip stuff for starter),

Based on the above, here's the very basics of TCP/IP

http://xahlee.info/linux/tcp_ip_tutorial.html
https://www.tutorialspoint.com/ipv4/ipv4..._model.htm
http://www.ele.uri.edu/courses/ele205/EL...torial.pdf
https://www.cse.wustl.edu/~jain/tutorial...t_2tcp.pdf
https://www.jameco.com/Jameco/Products/P...0Intro.pdf

thanks a lot always mothered  

if you don't mind,
can you please guide me which path should I follow after?

for example, study A, and then B, C
something like that

You're welcome.

Once you're educated with TCP/IP, you can move onto other network/Internet protocols such as UDP, FTP, SSL, SSH, HTTP/HTTPS and ICMP & ARP (both co-exist with IP). I've just named a few. I'd say start with HTTP & HTTPS and move onto others thereafter (no particular order). The objective Is to familiarize yourself with the communication and transfer of data over a network/devices.