I have heard from a few upper years we are allowed to sneak into certain buildings at night and study there. Is this true? or will we get in trouble? also where are good places to do this? Preferably places where there are white/chalk boards

If the building is open, then you most likely can. Otherwise you have to get in and stay there, as most buildings get locked and you wouldn't be able to get in after the doors are closed.

I've never heard of anyone getting kicked out just because it was late, unless they were partying or having sex. Some of the classes engineering classes, for example, are pretty balls to the wall and require you to stay in the building after hours (or even the whole night), plus there's grad school.

In addition to buildings locking, in some of them (such as MDCL) the elevators won't let you go up without a badge, and you also cannot re-enter any floors from the stairwell except for the main floor. In other words, you can get out of the building if you are already in there, but you cannot enter and cannot go up beyond the ground floor. Also in MDCL, sometimes security will come and kick out anyone without a badge. I'm not sure if other buildings have similar rules.

The student centre is open 24/7 though, and from there you can access most of the arts quad buildings, many of which have whiteboards or chalkboards in the classrooms.