I want to make a program in which you type a sentence and get a reply. eg. how are you ans- I am fine.(by saved sentences) which script should I use ; HTML, C,C# ,C++,CSS Python etc.?

Answer 1

Html and Css are no programming languages.
They are markup languages. Css is only style shert to make your website look better.
But you can make a website do just this. You can also do this in any programming language.

Answer 2

First of all, start with a basic one. You should use switch or if else structs of c#. When I started to learn C#, I coded a program on Console that makes a conversation with user. It's responses changes according to user input. I coded it with while, for loops and switch, if else structures.

Answer 3

I told you already c# is the best choice in this situation mixed with mysql database which stores the prewritten sentences.