Mixed Conditional Past - Present Examples: * If I had won the lottery, I would be rich. But I didn't win the lottery in the past and I am not rich now. * If I had taken French in high school, I would have more job opportunities. But I didn't take French in high school and I don't have many job opportunities. * If she had been born in the United States, she wouldn't need a visa to work here. But she wasn't born in the United States and she does need a visa now to work here.

That is probably because you don't understand ordinary conditionals. Take it one step at a time.