You definitely don't sound stupid. We've all had to start somewhere.

Owlie seems to have explained things pretty well. There's also another type of integrated break lever where you click the break to the side to shift to a smaller cog or bigger chain ring (I think that's how it goes anyway) and then there's another little sort of 'button' on the hood which shifts to the bigger cogs or smaller chain ring. I think this type is usually found on the more entry level road bikes (like my Felt F95).

And as Owlie said the gearing on a road bike is quite different from a mountain bike because the Mtb is made for different terrain and some pretty steep climbs (hence the triple crank).

Good luck with finding a bike. Keep us posted!