Fusion 360 can be used as a CAD environment. Fusion 360 is a cloud connected CAD tool, which means that you must upload files that are not created in Fusion 360.
Fusion 360 has various capabilities. Different capabilities are divided into Workspaces, such as CAM and Simulation. The Launcher is accessed through the Simulation workspace. The simulation workspace has a modeling environment called Simplify. The Simplify environment contains the simulation launchers.
Once a model opened in Fusion 360:
Geometry can be modified in any of the modeling environments. Geometry modified in the Simplify space can be done without affecting production geometry. The geometry changes in the Simplify space are done to Simulation Models.
There are tools to modify geometry specifically for simulation needs in the Simplify space.