i tried, i don't know how to make it look for my ancestors automatically
I'm not familiar with the website myself (my mother uses it), but to begin with you have to start providing information yourself.
If you're interested in genealogy then you should first start by asking your parents and grandparents.
Ask them what they know of their parents and grandparents and great grandparents.
Learn where they're from, when they were born/died, who they married, etc...
From there you can use that info to try and find people who match that information.