joshuakujawinski:
I am trying to understand how communicate with the MKR THERM SHIELD and UNO board or the computer.
The most important thing to understand is that this shield was designed to be used with the MKR boards, which use 3.3 V logic. If you check the "Recommended Operating Conditions" table in the datasheet for the MAX31855K, you'll see that maximum recommended Vcc is 3.6 V and maximum recommended input logic HIGH level is Vcc + 0.3 V. This means that if you connect the MKR Therm Shield directly to your Uno's 5 V logic level, you will damage the MAX31855K. You need to use a level shifter to reduce the 5 V to 3.3 V. You could do this via a resistor voltage divider or one of the level shifter modules that are available from any place you would buy electronics parts.