1/ Computers are currently only as intelligent as the person using them. They can only do what you tell them to do (or they are programmed by someone else to do). We can simulate intelligence, making computers that can have a conversation that sounds almost exactly like a human (there’s a bit more about this idea here)
2/Computers aren’t intelligent because they cannot think for themselves. If we ask them to solve a maths problem by specifying very carefully what we want them to calculate, they will be able to do it very easily. However, you can’t ask a computer a philosophical question and expect it to provide an answer. They are good at doing what they’re told basically, but not good at thinking for themselves (yet).