האם is a question word that comes before a yes/no question, but it's more of a formal form. For the informal form you just say the sentence as it is a fact, but in a question toning. For example: "האם אתה בא?" Means "are you coming?" But in a formal way. To a friend you can just say "אתה בא?"
You are talking about the the letter Vav. If the vowel marks were added, which they are not in modern hebrew, you would see that there is a dot in front of the vav. That gives it an "oo" sound. if the dot is on top of the vav it gives it an "oh" sound. I'm fairly new to Hebrew myself so I"m not sure if there is a better way to explain that or a better way to know how to determine when it is used as a vowel or the actual "v" sound.
Hope that helps.
If you're just taking a regular lesson and not a test, you can hover over/tap any word to see a peek at its definition. New words are underlined in orange, while old ones should be grey. For example, I didn't know what הוא meant, so I clicked on it to see it meant "he". [2019/03/25]