Spanish church Low-poly 3D model

I imported the provided high poly FBX file into Blender 3.1.2 and it doesn't look anywhere near as good as it does in the promotional photos. The model has distortions in various parts of it such as the windows and doors. The structure reminds me of a badly imported SketchUp file. The terrain is sloped in such as way as it will not easily fit into games/simulation terrain. This model has great promise, but needs to be re-worked to get rid of the provided hill terrain, which accounts for most of the polys, and for the structure itself to fit onto flat terrain. There were so many issues with this model I found I was unable to use it.