Interior Decorator or Interior Designer. They’re very different things.

• An Interior Decorator decorates spaces and requires no certifications.
• An Interior Designer does basic designs of Interior spaces (here’s the bedroom and here’s the kitchen) and requires a basic certification.
• An Architect designs buildings (here’s where the HVAC is going to be and this is what the roof is gonna look like) and requires a higher degree of certification.
• An Engineer designs the structures that support the building (here’s the engineered I-beam, and you require a drainage pond there, and you need a support column under that wall, and the foundation needs piers this deep) and requires the highest level of certification.
• A contractor ignores all of these people and fucks shit up