A 50mm lens is not wide-angle on a Canon 1200D. Because your camera has a crop sensor, 50mm behaves more like a short telephoto view, so it will show less of a room than your kit lens at 18mm.

For interior and real estate photography, you usually want a focal length shorter than 18mm on your camera. Your 18-55mm kit lens is already wider at 18mm than a 50mm prime. To capture more of a room when you can’t step back, look for an ultra-wide lens such as a 10-18mm or 11-20mm style zoom made for APS-C cameras.

A zoom is often more practical than a prime for real estate, because room sizes vary and you may not have much space to move. A 50mm f/1.4 can be useful for portraits or detail shots, but it is not the right choice if your main goal is fitting entire rooms into the frame.