The word sheath refers to something that is meant to cover something for protection. The usual uses for a sheath would be to cover and protect the blade of a knife, sword or dagger.
In a sheath,that is what the sword case is called
a sheath
A scabbard is a sheath, typically made of leather or metal, that is used to hold and protect a sword, knife, or other bladed weapon when it is not in use. It helps to prevent the blade from becoming dull or damaged and provides a safe way to carry the weapon.
A scabbard is a sheath for holding a sword.
sword..
you cover it with a sheath
Scabbard
When putting away a sword you "sheath" it, or put it back into its sheath, usually worn on a belt or sling.
yes
The plural of sheath is sheaths. As in "the knight sheaths his sword".
That belt is called a "sword belt" or a "scabbard belt". It is designed to secure the sheath and sword in place and make them accessible for quick drawing.