[Kernel & Development] Help needed

Who am i

I am from The Netherlands, 22 years old and currently studying an programming course in my country.
I just started year 2 of my course (total 4 years) and i know the programming basics of:

- Java (Object Oriented)
- SQL

Purpose of this Thread

I love android. I love it so much that i want to build my own ROMS & Kernels. However, maybe this is a stupid question, i absolutely do not know where the F*** i need to start....

Lets say i start at the basics creating my own Galaxy S6 Rom. How do i write scripts? How do i create a Unified Build (for all S6 models) etc. etc.
This above question might be tooooooo specific, but im talking generally about how to build a rom.

Ive been though a few guides (included a few from XDA), but seriously, it seems these are outdated...

What i am asking is DEFENITELY NOT an "Personal Trainer" who can assist me with every thing i need to do..
BUT i really appreciate it if someone can provide me with some nice resources, tips, tricks, links, guides and examples.

I feel kinda stupid because i probably getting some comments bellow here saying that i need to "google" properly..
But i seriously ask for some help here.

Hope you understand so you can help me a hand over here:)

Read me

- If this thread isn't allowed, please close it.
- if you have nothing useful to say that isn't going to help me, please say nothing or PM me..