HC-SR04 and ESP-03 8266

Hello! I'm working on a project with my ultrasonic sensor and Esp, I've been looking everywhere but I'm too confused. May someone please help me understand this. The code for my arduino and ultrasonic sensor is working fine, but now I'd like to broadcast it over to thingspeak.com , and I'm wondering if someone could write the code/find a blog and whether I should upload to my arduino or ESP, thanks

Iacopo