Would a Cinema 4d model keep good graphics when imported into Unity?

I’m planning on working on a cutscene/ animation however I’d rather buy a model, If I were to use a model like this would the same quality remain in Unity? I’d rather know before I spend my money.

Yes, if the only thing in your scene would remain that very model.
If you plan to use it in actual gameplay, consider also getting a low poly model with 5.000-10.000 polygons with baked normal maps.