You can do Comp Sci through Arts, it's the same thing (you can do co-op and same req courses). As for 1st year and 2nd year courses theres: {110, 210} that are the actual programming/creating stuff courses, {121,221,213} that are more of the algorithms and design courses.
Now for me personally, I did terrible in my first year courses in general but looking back 110 and 121 weren't too bad. If you do homework and keep up with things (even if u don't understand 100% of the stuff) you can pull off A-s easily. (I got Bs cause I was dumb)
As for second year, it comes down to a) your interest and b) your profs.
I was into creating shit so I aced 210 ( got an A) but 221 (algorithms) I got destroyed and barely managed to pass due to the prof being ridiculously hard (Class avg was around 61).
Now to answer your question in general, a 3.2 is good and getting a B or above is certainly not difficult. I've noticed that class averages hover around 70+ as I got into 3rd year. But definitely you have to keep an eye out for some profs, you'll hear some names (aka Wolfman, Patrice etc etc) that are the hard profs and generally it may be a good idea to avoid them.
If you want to check class averages theres a site for that.
https://webprd01.pair.ubc.ca/reports...request.action
Or google Pair grade distribution ubc. You need your CWL login.
If ya need to know more, holla. Hope to see u on campus in Jan when I get back LOL