You can hear 비 and 피 in google translator. https://translate.google.com/?#ko/en/%EB%B9%84 https://translate.google.com/?#ko/en/%ED%94%BC

you could probably tell from the context of the sentence like normally you don't say i got cut and rain came? sorry if it didn't help I'm not native but i just thought probably

Haha, yeah, I couldn't resist that as an example.

not too hard for saying it. pick up a piece of paper and put it in front of your mouth when you speak and compare the two. feel the vibe with ㅍ and the lack of it with ㅂ. get your ears to tune into it can be very tricky matter though. may take you many many hours.

Probably NOT 피를 피하다... I was typing with one hand and wiping coffee with the other!