I think I got the basic idea. The only problem is I'm mostly a beginner and whenever I'm try to create any routine, I always refer to other code and not writing my own. The way I went about coding is referring to other code, looking for likely solution and modified it to suit what I need to do.
I got what you mean and I do did practice it like that. However, my situation is not that I'm working a file on my own from beginning, rather that what would I do if I got that drawing from someone like I attached. When I got that drawing, making that layout into xref is just a hassle and time consuming.