I don't think learning to write blog posts is particularly different from learning to write anything else. To the extent that that is true, I'd refer you to Stephen King's book On Writing[1]. Specifically, one bit of advice from that book (loosely paraphrased) "the best way to learn to write well is to read a lot and write a lot".

The other book I'd recommend is The Pyramid Principle[2] by Barbara Minto.

[1]: https://www.amazon.com/Writing-10th-Anniversary-Memoir-Craft...

[2]: https://www.amazon.com/Pyramid-Principle-Logic-Writing-Think...

A great book that helped me was "On Writing" by Stephen King.

https://www.amazon.com/Writing-10th-Anniversary-Memoir-Craft...

Stephen King's rule is that the second draft of his book should be ten percent shorter compared with the first draft.

Source: his biography On Writing (http://www.amazon.com/Writing-10th-Anniversary-Memoir-Craft/...)