Dialog bot for tg in php?

Question

PHP

Hello, it never occurred to me how to implement a dialog bot. That is, I want other available commands to be given to him after a certain message. Perhaps not explained clearly. Example
P: Hello
B: Hello, write the genre of music.
P: pop
B: Write artist
P: Maxim
B:
P: back
P: maxim
B: command not found

Answer 1

The example is also not very clear))
The implementation is normal: search for a pattern match in the text sent by the user and then if-else, depending on the match found.