Assuming you have a Gen I Cruze, here are a few of the possible fixes depending on what is actually wrong:
1. Check your coolant level. The system may not have been "burped" completely. Refill as needed. Nice reply by Jblackburn to a similar issue. If you are able too, pressurize your cooling system to find any extraneous leaks.
2. Use an app like Torque or a ScanGauge etc to see the actual coolant temp.
3. Make sure the water outlet is not cracked
4. See if the thermostat is working - see video 3 below for place to check.
5. Determine whether or not the water pump is leaking. There is a TSB for this for some models