In order to use adsense, you need a self-hosted website. In other words, you need a domain and hosting if you want to use Adsense. However, there are ways to use Adsense to make money without actually owning a website.
You can use Adsense on Youtube. In order to use Adsense on Youtube, you will have to create a channel, upload videos, generate 4000 hours watch time and 1000 subscribers and then apply for Adsense. Adsense approval through Youtube is easy.
You can also use Adsense on Blogspot blog. In order do that you need to create a a blog on blogspot. The blogspot blog is associated with your gmail. Once you create a blog, publish original and well written contents and apply for adsense.
Hubpages dot com is another site where you can use Adsense without having a custom domain and hosting.