What are scrolls? What are potions?
Scrolls of Turning, Scrolls of Teleportation, Potions of Holy Water and so forth are objects that can be purchased in shops, and can be used from the More Commands screen (sometimes requiring other conditions such as the presence of other vampires).
You can see what you are carrying from the My Vampire screen, and also get descriptions of the objects by moving the mouse pointer over the questionmark icon next to each object (which is also available in shops).
Questions regarding the specific effects of each object will not be answered here. Experiment and find out for yourself.