ㅃ is always pronounced slightly harder than ㅂ. It is very tight and tense. ㅃ, ㅉ, ㄸ, ㄲ, and ㅆ are called fortis (strong) consonants, whereas ㅂ, ㅈ, ㄷ, ㄱ, and ㅅ are called lenis (weak) consonants.
I think it's one of those words that have the same name, but different meaning
The pronunciation is similar, but bread is "p" and the "b" in this case is stronger.
방을 is room as an object and 방이 is room as a subject. 을 and 를 are object markers and 이 and 가 are subject markers. 은 and 는 are emphasized subject markers