Hi S.,
I am a mom and a Child Development Specialist. This advice is from a mom and a professional!
You do not have to worry at all at this point. What your baby needs most during the first 12-15 months is breast milk. Before he turns one he barely gets any nutrients out of anything other than breast milk. He really only eats other foods to learn how to eat them and to partake in the social ritual of eating with a family/friends.
The best way to introduce your baby to eating is to sit him on your lap during all meals (you don't need a high chair/baby seat at this point). Offer him the breast during the meal if he wants it, but it's okay if he refuses. Eat your meal normally (this is a bit tricky but it models the process for him). You can set a few pieces of cereal (Cheerios, etc.) in front of him, but it's not important whether they make it to his mouth or not. As he gets older and has more teeth you can start cutting up everything you eat into very small and soft portions and put those in front of him (Just one or two pieces at a time). Eventually your baby will be past one year and will be interested in sitting by himself and feeding himself all of the wonderful foods you're eating.
You really don't need to feed your baby cereal (the runny baby cereal). It will not give him any nutrients and it is confusing to have a runny liquid put into his mouth while he is still nursing. And you definitely do not need to use "baby food" for any reason...save your money!
This may all seem a bit strange to your MD but I learned it from my MD's from Homefirst...and they learned it from many, many women over the past 30 years. Plus it is what I learned in graduate school and it is what has worked best with 2 of my 3 kids (the 3rd is only 10 weeks!)
I hope this helps!
T.