How To Get Data From Arduino Uno Onto My Laptop Through The USB
The "Serial Monitor" is merely a window to the Arduino's serial port. You don't have to use it to use Serial. It's just a (very simple) built in way of seeing the data.

You can use the Serial interface with your own software, or with third party software. It's not tied to the Serial Monitor in any way at all.

So:


Use Serial.print() etc to send data to the PC
Write your own PC software in your language of choice to process that data, or
Use some third party application to read and process the serial data