Hi mr kira and welcome to Webmaster World!
If you have a YouTube account, go ahead to your Studio settings and check the box next to "Enable Monetization". There you will also find a guide from Google that will show you all the steps you need to follow to start earning money with your videos.

As for DFP, you don't need it to make AdSense work. DFP is an ad server, which might help in the future as your yield management will get more complex over time.

If you just have a blog or website, there is no need for you to go through YouTube. Just create an AdSense account and you're good to go, once it gets approved. Remember though, only create the account (or re-submit an old one for review) once you know that you have already created great content for you visitors. The AdSense team doesn't give away accounts to anyone - just to those who made an effort to create something of value.

Use the search bar in the top-right corner to search the forum for similar topics. You will find lots and lots of answers here. Again, welcome!