If you get an older dog, already house-trained, it should only take a day or two for it to get adjusted to the new home. If you get a puppy, or a dog not house trained, it may take up to a few weeks before it'll learn to go outside. The best thing to do is take your dog out for a walk several times a day when you first get him. These two things together will give him an opportunity to go outside and help him to learn not to go inside. It's extremely important to walk your dog at least twice a day.
Some dogs only require it once, but most two or more walks are needed.
The best situation would be to have a backyard with a fence. Then you could just let your dog exercise and do his business there, instead of having to walk him. Even if you do have a great backyard, you should still take him for a trip around the block when you can. Feeding is an important job as well. If there is a young child, older than 8, it would help encourage responsibility if you let them take care of the feeding.