Any YouTube topic recommendation?

Wanna start my own video blog on YouTube, but have not decided the topic yet. I have few options in mind:

educational (helping students with their applications for studying abroad).

cryptocurrencies (making videos about cryptos, telling people how it works, how they can mine, etc.)

book tube (since I am reading a lot of literature, I thought maybe I should start my vlog about books, tell people what I read, which books I find interesting, etc.).

What would you suggest, or what would you like to watch?
Thanks for the ideas and comments!

You can go for online marketing or earn from home type channels which would help people to earn and that would get a lot of hits if it gives genuine informations

I think book tube has the biggest potential with the smallest investment, though I'm not sure how many people really look at reviews.
Crypto is pretty saturated, all these gurus and shit everywhere, BUT if you can make e x c e p t i o n a l videos I think you have a chance to grow a channel fast. But I really really do mean exceptional, like Kurzgesagt or what ever their name is, their channel picked off pretty fast, but the videos take a long time to make.
Can't say much about educationals, since I never really looked into that topic.

As reading literature is something you like doing, I'd go with that. Just make better higher quality content than your competition and your channel will always grow. Kinda hard to monetize that traffic though, they are in buyer mode, but for a cheap book written by someone else.
On the other hand, if you would use the channel to promote your own works in literature that could turn profitable.

A travel blog with every detail, from how you had gone to the hotels to stay at, visiting places and all. If you could travel yourself, it's better.