Don't Worry! This is a common problem and usually pretty simple to troubleshoot yourself. If you have low water pressure or no water flow you should check out a few things before call a technician out.
1. Make sure the water valve is turned on.
You can open it all the way or adjust it to your desired pressure.
You can usually find the water valve underneath the sink, or sometimes on a rare occasion, it may be located in the basement.
2. Make sure your refrigerator is not sitting on the waterline. Sometimes when installing or moving it around this can happen.
If all else fails it is time to call an experienced company, such as Citi Appliances because there is most likely some other issue causing your problems.