There are lots and lots of buildings in Lumion, each with different functions. You can use them to create more realistic backgrounds in your renders.
There is also a grid option in "Utility" tab. You can place it to establish some points of reference and then delete it in the end.
Download Lumion software here: https://support.lumion.com/hc/en-us/a...
I am using a student license for Lumion Pro 12.3.1 through my university affiliation.
Good luck!
Arghavan