...and I am afraid you're too late to keep the orange colour for this year. If you start feeding colour in the middle of the moult you'll get a some orange feather and some yellow. If you want the orange colour you need to feed the colouring food before the moult starts till after the head (the last to molt) is completely molted out.
You should have been told that it has been colour-fed when you got the bird.
Canaries are easy to look after. Just the basic canary seed mix is excellent food. Clean water daily and a piece of cuttlefish bone on the side of the cage. Canaries don't need grit because they shell the seed. Whenever you are preparing veges, just stick a little bit between the wires - and remove any that's left after 12 hours, so that it doesn't go bad.
Management is mostly common sense. No full exposure to the full sun unless half of the cage is covered with a dark cloth so the bird can get out of the sun when it wants to. Be careful of any draughts, they are lethal to small birds.
Canaries can easily live for 8 years.