In general, yes, respiratory distress = raise the HOB.
However, in NCLEX world, they aren't always going to ask you what to do first. They might ask you what your priority is or what the most important nursing intervention is. These answers may be very different from what you would do first.
Futhermore, some patients may not be able to have the HOB raised, such as a patient in spinal traction.
In NCLEX world, it's very important to read the question thoroughly and first determine what they are asking, then make your selection based on the information provided. Don't give yourself broad generalizations like "Raising the HOB is always the right answer" because 99% of the time that will come back to bite you.