Serial.read(); //used to read the user inputs
x == Serial.read(); //takes the height inputted and placed inside of the given equations.
The above code doesn't do what you seem to think it does. "==" is a comparison operator, and Serial.read() returns characters from the serial port.
I suggest to learn about data input from the serial port, or serial monitor by following this tutorial: Serial Input Basics - updated
If you are thinking of inputting data from the keypad, that uses a different approach.
For the time being, drop all the extra equipment, and focus on learning how to input data.