C# Coding approach

Question

So when coding, we have our own approach that's different from other people.
So my question is, when making an application, does it have an effect?
For example my code is 1000 lines long.
While the other one can make it with only 100 lines.

Answer 1

Maybe there are many different approaches, but there are also well proven and established guidelines, principles, and best practices, which are usually followed by all developers, like
KISS = keep it simple stupid
DRY = don't repeat yourself
SOLID => this is more complicated to explain but it means how to effectively apply the concepts of object oriented programming in software development.
Clean Architecture = segregation of the functional areas of the program

Each of these topics have books written about them, and you can research google / wikipedia for more detail.
It is very useful to get familiar with all of them, because then you will speak the same language as any professional developer.