Remote Control with http post for bot

hi
I want to start using selenium with any browser that allows me to send commands and
receive values ​​from a web page (that I did not developed), as a kind of bot,
but using HTTP POST.


schematically:

Send command POST
My program language X  --->  something here  ---> Browser + Web page


Receive response (json, HTML or txt):
Browser + Web page  --->  something here   --->  My program language X


is only permitted HTTP POST because language X is not java, not c#, not python, etc.
is 4th Dimension

Commands sent by POST are for example: press a button, HTML field contents read,
write an HTML field.
The answers are mainly getting values from field/objects HTML
Selenium is suitable for this?
What should I install on the Browser ("something here")?
Where I find documentation to control the "something here" with HTTP POST
thank you very much

(Sorry, english is not my native language)

Some kind soul guide me?
Or tell me that I can do this program.
thanks