Quick answer
Б б is the b of “bed”. Do not confuse it with В (v) or with the soft sign ь, which has no lid.
Бб
Бб
b
братbrother
How to say it
Exactly the English b. At the end of a word it devoices to p: хлеб sounds like “khlep”.
братbrother
бо́льшеmore
буты́лкаbottle
хлебbread
спаси́боthank you
футбо́лfootball
Б, В and ь side by side
Б has a flat lid on top. В has two closed bellies. ь has a belly but no lid and is never capitalised. Written small: б has a tail going up, в does not.
Devoicing at the end
хлеб is pronounced “khlep” and клуб as “klup”. The spelling keeps the Б because the related forms need it: хле́ба, клу́бы — where it is clearly b again.
Typical mistakes
Reading брат as “vrat”
“brat”
Б is b; В is v.
Pronouncing хлеб with a clear b
a final p sound
Final voiced consonants devoice in Russian.
Check yourself
Which word contains Б?
брат — brother.