I was commissioned to work on a bird's eye view, but as shown in the image below, I need to implement a sloped land rather than a flat land. However, since the modeling program is SketchUp, it is difficult to implement a naturally sloping land.
You can use the landscape object in Twinmotion and sculp the land to your need. You can then position the houses as individual elements on the landscape.
Try using the Sandbox tools in Sketchup and the Drape and Pedestal tool in Sketchup for your terrain. There are also a few good Sketchup site grading plug-ins.
Good luck trying to get much detail landscape grading with the TM landscape sculpting tools with the amount of Sketchup objects the image shows that are intersecting the landscape. The TM sculpting tools are best used to sculpt adjacent terrain as the accuracy of TM sculpting is limited.