Ants in the house are easy enough to remove. They invade your house in the first place because they find food! So, clean thoroughly!
Yes, caulking visible cracks is an important second step.
Use ant baits or try a natural deterrent like sprinkling dry Cream of Wheat -- it's indigestible (and lethal) to ants. Sprinkle it around your room's border. See if that helps.