just to let you know, you probably want to learn cork 7 first, then cork 5, then cork 3.
cork 3 is a super technical trick. you are probably doing a really shitty 3, or some kind of weird flat 3.
i know tons of people who have tried 'cork 3', but to do it properly is fucking tough
for cork seven, do a normal 720, and drop your left shoulder (if you spin left) a bit, and spot your landing