Because mage spells are learned though study, you must have the correct Magic book to learn and cast a spell. Learning spells can be banked up. You do not wish to learn Detect Monsters, Phase Door or Light Area. You can wait until you are third level and learn both the Cure Light Wounds and Stinking Cloud, both third level spells. Spell failure and effectiveness is based on intelligence for Mages, Rangers, and Rogues.
Rangers can learn all but the most powerful offensive spell.
Rogues can not learn any offensive spell. Rangers don't get spells until 3'rd level, Rogues 5'th level. Mage Spell Descriptions Confusion - Confuses a monster for a short time. Create Food - Causes a food item to be dropped at your feet. Cure Light Wounds - Restores a small number of hit points.