how much traffic you get per day? thats your first start. you need to have visitors for your site for them to click on your ads. if your site is not interesting enough for visitors to visit or stay for long, you will not get any visitors or click. build site for human readers that will provide some values. if you can build a site like that, people will visit it and click your ads. you will have to promote your site as well to drive even more traffic to it
When I first got started with google adsense "Joel Comm" helped me out a lot. Google him, and watch some of his YouTube videos for tips and tricks.
You will hace to focus first in get some visitors to your site, with good keywords and some backlinks to those keywords
That's right, the only way to earn on Adsense is to get more traffic and to make any money, you need plenty of it