Long storyshort, you will become a greywarden, a lot of people will die, you pick up a lot of cool loot and most of the time your inventory will be full. If you happen to play on a console, most of the time you will be looking at a loading screen evertime you open a door. An assasin will try to kill you , sent from a man who is responsible from Duncan's death, your recruiter, and also the King's death.
You and another grey warden venture off to join forces of different races, elves or warewolves, dwarfs with or without golems, humans of course. You will face many choices that can lead to romances. Morrigan is extremely weird but very easy to lay, she is kinky so think Gothic and treat her like that and next thing u know , she will be all over you. You meet a Chantry Women in Lothering who wants your you know what, but she is very hard to sleep with, do not count on it until you kill her old mentor who wants her dead, and also be very nice to her... or u wont get any.
Wynne is an old hagg, if you want romance with her... then .. you are better off wasting your time with wooing Shale, who was once a Female Dwarf.