Quick question, is there anything from stopping me from taking a level 2 priest and having 1 beasts spell and 1 heavens spell?
Each Wizard gets to choose one lore ( unless they have a specific rule like wandering delibirations) From Page 29 of the WHFB Rulebook..... Choosing Your Lore The choice of which lore each of your Wizard models know for a particular battle must be made when choosing your army, as explained on page 134.