My grandmother used her tester on me my blood sugar was 477. is that normal?

No: Time to go see your family doc in a fasting state. Tell him/her what you just noted. You'll need to get re-tested which means another finger stick. If it's still high, you'll probably need blood drawn, especially if your vision has changed recently, you're more thirst than expected or urinate more frequently than usual. Normal fasting blood sugar should be less than 100. You may have diabetes.

No: very high, CCSee doctor asap as you are most likely diabetic.