im trying to plan a model of a house, i know a little about construction from highschool carpentry, but there are a few things i need a little help figuring out, first is the ridgebeam i want to put in it, can a ridgebeam be 3 and a half inch wide(i would scale it down, in the model it would 7/16 of an inch)? its the only thing i can think of to get the length needed for a 44 foot beam counting the lookouts(i figured on maybe doing it up the same way one would do door headers but i need some advice on whether or not that would work if this were a full sized house)

the next thing is rafters, can someone tell me a formula for laying out the cuts of a rafter? i need to know where to cut for the plumb cuts and birds mouth

can someone here tell me what i should do about the ridgebeam and rafters?