DiegoHG:
This is the link to the amplifier -> Adafruit Universal Thermocouple Amplifier MAX31856 Breakout : ID 3263 : $17.50 : Adafruit Industries, Unique & fun DIY electronics and kits
Those amplifiers use SPI so they will also connect to pins 11, 12 and 13 (MOSI, MISO and SCK) and will need one extra I/O pin each for CS
You should be aware that the Arduino 3.3v pin cannot provide much current and if you have several 3.3v devices you may need a separate 3.3v supply. That could be provided using an LD1117 voltage regulator connected to the Arduino 5v pin.
...R