Hi,
the Unity ECS (Entity Component System) and the GameObject world are 2 different systems that are not equivalent to each other.
Handles, such are the Move tool handle, are meant to interact with GameObjects and Component exclusively for now, as the Entity data does not have a editable scene view representation.
That's the same for the physics system. Using physics with entities requires to use a system compatible with DOTS, a package exist for this and documentation is available there:
https://docs.unity3d.com/Packages/com.unity.physics@1.3/manual/index.html
Globally, you cannot work the way it's currently done in the sample project and try to interact with entity the same way it's done with GO. I encourage you to read more about DOTS and the ECS system, please have a look at the ECS samples available here:
https://github.com/Unity-Technologies/EntityComponentSystemSamples/blob/master/PhysicsSamples/README.md
There is some great samples on physics with ECS :) but also others!
Have fun