Hi! Welcome to TWHL
The first thing you want to do is draw something on paper. Draw a floor plan with room names and doors and hallways.
Then you need to look at each room individually.
What's in the living room - Couch, chairs, tables, lamps, television, possibly an entertainment center, pictures on the walls, windows, curtains..
What's in the kitchen? - Sink, counters, drawers / cabinets, appliances (stove, microwave, refrigerator). Is there a bathroom? Is there a basement? Is there a bedroom? If you treat each room in the house as it's own little world, the details pretty much fill themselves in.
Aside from it being realistic, that really depends on the object scale and the texture quality. Feel free to post some development screenshots and we'll all be happy to comment and give some constructive criticism.
P.S. A lot of people like to use imgur.com as a host. It's easy and free!