You can get access to the UE4 Character Skeletal Mesh by clicking “Add New”, above the Content Browser. From there, choose, “Add Feature or Content Pack…”. Go to, “C++ Feature”, choose “FirstPerson”, then click “Add to Project”
From there, you can use the “SK_Mannequin_Arms” Skeletal Mesh in place of HeroFPP.fbx. There is also some animations and standard Skeletal Mesh assets, such as the Physics Asset and Skeleton.