Being smart and Intelligent are similar but the main difference between being smart and being intelligent is that when you're smart you're able to learn new things easily.
When you're intelligent you're already knowing those things that most people have to study to learn.
For example you could be smart enough to learn to become a computer programmer and program computers or write code.
But then again you could be intelligent and already know how to program a computer.
Before there was books or other knowledge on how to program computers someone had to first be able to know how to program computers.
So the first ever computer programmer would be intelligent but someone who learns how to program computers would be smart.
Me I could not learn to program computers or code websites etc even though I tried learning.