you need to learn how to make your own monster hunt game before you can get more advanced, if you can`t figure out the walking around bit then you didn`t understand what the monster hunt program was doing, inside a building or outside, whats the difference?, position a huge box over the monster hunt scene and you are inside an acropolis style structure, replace the pillars with wall sections and you are inside a building, understand how the code stops you going through the floor and you can work out how to climb ramps and stand on top of objects, start simple, add to it.
we know where area 51 is, but where are areas 1 to 50?, and what do they do there?.