my question is how can i apply an orange tint intensity of 40 to a photo

i tried to do part of it but am confused after that
Code:
file = pickAFile()
pic = makePicture(file)
w = getWidth(pic)
h = getHeight(pic)
intensity = requestIntegerInRange("What intensity?",1,99)
tintColor = pickAColor()
samplePicture = makeEmptyPicture(1,1)
samplePixel = getPixel (samplePicture,0,0)
...