In case anyone missed the live streaming on Twitch from BioWare, they archived it and made it available for us.
We can see the game from the very beginning, how one chooses gender, race and class first. You can pick wether you want to be a Dual Wielding rogue, Archer, Two-Handed or Weapon & Shield warrior. It will not lock you in but instead gives you starting abilities and equipment accordingly to what you chose. They include character creation in this video as well. They also explain it a bit more how importing data from the Keep into the game will work and show when you will have the chance to do so. However, they refrained from revealing the intro of the game in this presentation.
After the character creation, they load a gameplay which takes place in the Deep Roads, with a male human warrior, Cassandra, Varric and Vivienne, involed in a quest against the Carta and some templars. The gameplay is relatively long and they answer quite a few questions asked by fans, such as if one can use abilities outside combat. Some answers are also supported by presentation in-game.
In the last few minutes we can watch again the well-known trailer "Lead Them or Fall".
The archived stream can be seen here.