A mage wouldn't know what to do with a sword. In terms of objects that appear in the dungeon, you can search them, sometimes a floating window will come up that shows a pre-rendered 3D scene from a first person perspective. In that window you can give commands, like dropping items, pressing buttons, using objects in the window. These commands can have various effects depending on the scene. For example, using the empty bottle on the cauldron window might allow you to draw some of the cauldron liquid into the bottle.
Characters always attack with the currently equipped weapon.
If no weapon is equipped then the character attacks with the currently active spell. If there is no currently active spell, or the character cannot cast the current spell for some reason, then they resort to bare handed attacks. The basic commands are Move, Attack, and Stand Ground. Move means the character will proceed to the destination location, and ignore any monsters or attackers. Attack means the character will attack the selected monster until it is dead, or if you Attack to a particular location, the character will proceed to the destination location, but will stop to attack the nearest enemy if one presents itself.