as a program which one should I start to learn btwn c, c++, and c#.

Answer 1

1 :- c
2 :- c++
3 :- c#

Answer 2

1. C
2. C++
3. C#
The reason I suggest this order is because C is the way to learn memory allocation, socket communication, interproccess communication, forks, threads etc.
C++ is object oriented so it seams like a natural step
C# is pure object oriented. Almost everything is an object with predefined methods that you can use to make your life easier, but it comes with a price: the user has to have .Net installed and it's not as fast as C++ (although the difference is not significant)

Answer 3

c

Answer 4

c

Answer 5

i think c# is better to start first with