Below is a list of suggested reading and MOOCs on statistics, which are very useful for me. They are classified into three levels, namely Beginner, Intermediante, Advanced.

Beginner

Intermediate

Advanced

[Book] All of Statistics: A Concise Course in Statistical Inference (Springer Texts in Statistics)

This book was written specifically to give students sound understanding of modern statistics, and its coverage is very wide. You may skip the proofs in this book. I use it as a reference book. When I am not sure about some concepts or techniques, I would read the relevant chapters.