The DerivedDataCache folder is in the install directory of the UE4 engine version you are working in (UE4.14, UE4.15, etc.) When you delete this folder it will rebuild upon restarting the Editor.
As far as the errors are concerned, I’m basically pointing out what is causing the build to fail so you can research these errors online. The first one appears to be a problem with a mesh or plane imported from a 3D project or made in the editor.