stk500_recv(): programmer is not responding

I am building a Elegoo Smart Robotic car v3.0 and the software I am using is Arduino, so I got a account and then when I uploaded it it said programmer not responding. I have a UNO R3 and it seems to not be working. If you know that error and have a solution please post it so I and other people may use it to fix this bug.

Thank You,
jaffery1