C++ - Call a specific function after inactivity of a time period

I'm trying to get mind around this problem. Possibly I may be taking an incorrect approach.

I would like to make a dog detector so if a dog hasn't hasn't been for 10 second (inactivity), the program would turn off a light. The idea is to run a specific function after a specific period of inactivity based on an if condition.

The goal is to run this code without interfering with the main program. I understand i could use threads. However, my current approach is still interferes my program /sensors.

My Approach (pseudo-code)

  if(detect_object == dog){ 

    std::cout << "Dog detected"; 

    }else{

   std::this_thread::sleep_for(std::chrono::seconds(10));
   //Turn light off

    //If Dog is not detected after 10 seconds. After waiting 10 seconds turn light off. Without delaying the the program
    std::cout << "Dog not detected, turning light off"; 

    }

Thank you!