that’s easy
save the image in the folder where the sketch is
look at loadImage() in the reference and then at the image() command
https://www.processing.org/reference/loadImage_.html
Example
PImage img;
void setup() {
img = loadImage("laDefense.jpg");
}
void draw() {
image(img, b.xPos, b.yPos); // your bird !!!!!!!!!!!!!!!!!!!!!
}