Hi Gerri, welcome to DC. You are doing just fine! Relax and enjoy - we are a pretty friendly bunch here.
Vol au vent fillings can actually be quite simple. A classic is a basic "chicken pot pie" filling with small pieces of chicken breast or thighs in a gravy with small vegetables such as peas, carrots, onion, etc. You can even use frozen mixed vegetables.
I have also taken a piece of cheaper cut beef such as stew meat or round steak, cooked in a crockpot or covered in the oven with onions, mushrooms, a bit of beef stock and seasonings. You can even use BBQ sauce. If you do it in the oven, just make sure the temperature is low (250 - 300) and cook is slow and make sure there is sufficient liquid.
Any stew type filling works well.
Let us know what you decided and how it went!