Hello guys, first of all, I think you better look into what niche you're interested in order to get better results. Popular niches are saturated with great content. And if you're not genuinely interested in creating good content for those niches, you won't videos would just be a waste.
Otherways, here is the The TOP 8 niches for youtube videos that you may earn alot from it:
2. Celeb gossip
4. Top X lists
5. Fail compilations
6. Food reviews
7. Product unwrapping/opening
8. How to...
It's not hard to get views and subscribers on YouTube with any of the above. But if you're looking to monetize something you really need to focus on niche and quality.