Any good resources for learning R2DBC or its Spring Data R2DBC Implementation?

Question

Usually I am pretty good at finding resources on learning, but I am having trouble finding good learning resources for R2DBC or its implementation Spring Data R2DBC. So I am looking for a good resource - my definition of a good resource is

it explains everything in a well-rounded manner , not only just how to use it, but when to use what and what general functionalities it contains. It doesn't need to get too deep into the implementation details but enough for programmer to reference later based on the use cases.

So seeking help here. Thanks

Because I lack knowledge on database connectivity libraries in general, I first tried to get a head start by reading https://www.marcobehler.com/guides/java-databases. It gave a pretty good introduction on the JDBC side of things and I think similar concepts applies to R2DBC. So I am looking for something that can explain the ORM side of things as well as when we want to do it lightweight and just write plain SQL queries.

I tried:

1. Looking on Youtube - it is mostly on the application within a specific project and in the videos I saw people just use ORM without explaining in details - such as what is ReactiveCrudRepository and when to use it
2. Google Search - things such as https://docs.spring.io/spring-data/relational/reference/r2dbc.html only gives some quick overview in specific areas (I think it is still tailored towards people who already have experience or looking for a quick start).
3. Book - there is only one book on this and somehow the reviews are mixed

To summarize, there are a lot of resources that I can grab pieces of information from but just doesn't seem to have any go-to places for general referencing/learning.