“Raise” is the more general of the two words. Both it and “lift” mean to bring something above its original position. You could say “Raise your arm” just as correctly as you could say “Lift your arm.”
However, each word is also used in a variety of specific instances. You raise a flag, you don’t lift it. You sit on a ski lift, not a ski raise. You raise children if you’re talking about helping them grow up; you lift them if they’re short and can’t see the parade.So once you get into the nitty-gritty, it’s best to check a good dictionary.