So I created a new character and wanted to become a vampire lord as quickly as possible. Right after escaping I ran to Whiterun and clicked on guards over and over trying to start the Dawnguard quest. Non of them mentioned it. I traveled all over Skyrim and still no one is talking about it. I tried finding the entrance to the Dawnguard fort by going to where it should be and I still can't find it. Is there some kind of prerequisite I haven't met yet?

You need to be level 10.

Thank you.

You're welcome .

No you can find it yourself. Just find Black briar estate, you can find it on your own or by doing a quest to get Frost. Go down the road from the house and to the left is dayspring canyon. Go through there to get to fort Dawnguard.