Have a serial number, but cant find any documents?

Hi everyone, I'm stuck on something and I was hoping someone could help.
My husbands grandfather: Richard W. Huard, DOB 1/21/22, Massachusetts
From what we know, (and it is very little), is that he was enlisted on 11/24/42 @ Fort Devens, MA serial no. 31255869
 
I have accounts with ancestry.com, and fold3... and Im coming up with very little. (frustrating!) I have a document off ancestry, that is titled US Dept of Vet Affairs BIRLS Death file. (that gives his death date, which is accurate). The only other thing we know, (or that we think we know) is that he could have possibly been some sort of medic? Before he passed he had one conversation with my daughter where he said he was a 'doctor on the ship'.
 
Is it safe to say, (and  i apologize for being naive), he actually served in the war? Meaning, (aside from the converstation with my daughter) he didnt just enlist, but did in fact serve?
 
.. if so, Im wondering why Im having such a hard time finding ANY leads on this solider at all. I'm relatively new with playing this sort of detective, but have had nice success with the resources ive been using.
 
Scott? help? hahaha :)