What does "race against time" mean?

What does “dweeb” mean?

The word "dweeb" is a noun used in slang to refer to a person who is physically and socially awkward and lacks confidence. It is often associated with being "a nerd" or a "geek". It is not a compliment and could be considered offensive, so be careful how you use it. Ex: I always feel like a dweeb when I go to parties. Ex: I don't want to invite him. He's such a dweeb.

Is it natural if I change "head home" to "go home" here?

Yes, the two expressions mean something very similar. You can often use the words "head" or "go" interchangeably. Ex: I'm going to head home at noon. Ex: I'm going home at noon.

What does "just" mean?

"Just" in this context is an adverb that means "only" or "simply". In the case of the video, "just" is used to emphasize that the most important thing they all need to remember to stay focused. Here's some more examples of "just" in this context: Ex: Just don't forget to meet us for dinner at 6:00. Ex: If you need help, you can just call me.

What's "the curve players"?

"Curve players" are players that have set a high standard for other players due to major achievements and accomplishments. This is because these players were or are incredible in their sports. For example, in baseball, Babe Ruth is considered a "curve player" because he was the first player to ever hit 500 home runs in his career, among many other accomplishments. Michael Jordan is considered a "curve player" in basketball because he was a 14-time NBA All Star, among many other accomplishments. These "curve players" are players that many athletes admire and aspire to be.

I don't know well about the role of "with" here.

Here, "with" is a preposition that shows possession. He is saying that when he woke up, he had (possessed) three days until the deadline. Ex: Go talk to the man with the hat, maybe he can help you. Ex: I was born with curly hair.