Sounds like you have everything you need.
Good work wiring up the lights.
You have pretty much the same setup as me except i have the WS2811 LEDs.. basically the same however.
Copy my code in post 3, and then use the app to scan the QR code to get the project widgets.
Update these line:
char auth = "xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx";
Blynk.begin(auth, "xxxxxxxxxxxxxx", "xxxxxxxxxxxxxxx");
FastLED.addLeds<WS2812B, DATA_PIN, GRB>(leds, NUM_LEDS);