You have to create a HTML form (on your page) not just input. read about it here
I use ESPwebserver.h to handle url requests.
The easiest is to let the forma action direct you back towards the same page, and then you can read the form arguments using the .hasArg() and arg() functions. Since the .arg() function returns a String you will have to convert the input to an int using either using .toInt() or with your own function (.toInt() returns 0 for incorrect input, if 0 can be a correct input and if you want incorrect input to be ignored your own function is better)
Thank you! it was exactly what I was looking for!
But now I have another problem, when I go to use the .hasArg() function it returns me the error:
'class WiFiClient' has no member named 'hasArg'
Actually, client is my WiFiClient: "WiFiClient client = server.available();"
Could it be a problem with libraries? I have updated them with the latest available for the ESP8266, the following libraries are loaded in the program:
#include <stdlib.h> used for string conversion
#include <NTPClient.h> For the NTP Time
#include <DFPlayer.h> DFPlayer mini