In the US and Canada, wire colors are:
- Neutral = White (or occasionally gray)
- Ground = Green, Green/Yellow or bare
- Hot = Black, Red, Blue, Orange, Yellow, etc.
You appear to have two hot wires in the ceiling. There are a number of possible reasons. One of the most common is for a fan with a light, where a separate switch is used for the fan and for the light. Assuming that is the case, you need to find out which wire (red or blue) is connected to your switch.
(With power off at the breaker, of course...)
Remove the switch cover plate and pull out the switch.
See what color wires are attached.
If there is exactly one of red or blue and one other wire (typically black) then you have your answer. Connect the red (or blue) wire to your light, cap the other with a wire nut, connect whites together, connect grounds together, and you're done.
If the switch has both red and blue, then something else is going on - upload pictures and we'll try to figure it out.
If the switch has neither red or blue, then something else is going on (or you have the wrong switch) - upload pictures and we'll try to figure it out.