I can only comment on politics as I didn't do history. Really not much to it in first year, if you go to most of the lectures and get your essays done to a decent standard you shouldn't have a problem. Also, don't waste your money on the books they tell you to buy, I could probably count on one hand the amount of times I used them throughout the year.
Your meeting with the advisor of studies will be to pick your other subject as you need to do 3 in social subjects. I got strongly advised from someone on p&b NOT to do sociology yet I went ahead and picked it. Worst decision of my first year, I urge you not to do the same