[Discussion] I have been studying hard for introduction to Statistics, what helped other people to understand this area of math?

my teacher is ruthless. He lacks compassion for me because I started 3 weeks late in the semester and now my mark is at 40%. I have to get 22 marks out of 30 to get a passing mark. Anyone please put your input to help me out. I have been studying like crazy but I think im missing a piece to the puzzle.