I hit level 50 the other night. My home Lakeland Manor had a ancient dragon. Left for 7 days and came back, it was still there flying around. Lydia and I can kill them but can take several dozen tries. The last two I had chase me Falkeath and with the help of the local guard kill it. Went back to Lakeland Manor and a second one shows up? How do I get Dragonrend? Do they have a quest to kil all the dragons? I read I can go to Throat of the World and get Dragonrend. That is today's research. How do find the path to get it.

You will get that shout by following the http://www.uesp.net/wiki/Skyrim:Main_Quest. It's the one that started at the beginning of the game and directed you to Riverwood after you escaped Helgen.

Thanks.

Resist magic (and resist fire or frost) potions and enchantments on apparel are extremely useful when fighting ancient and the stronger dragons added with Dawnguard until you are able to get that shout.