“Would you be able to help me put it together?”
You have to give a presentation to several executives at your company. You need some help with creating a nice-looking presentation. You are asking a coworker who's good with design to help you. After explaining the situation, you ask this question.
Would you be able to help me put it together?
This is a rather polite way to ask someone to do something. It's polite because the phrase "would you" is less direct than "Can you" or "Will you". You ask "Would you be able to ___" when you're asking someone to do something that is a bit inconvenient:
Would you be able to give me a ride home after work tomorrow?
Would you be able to send it to me by two this afternoon?
In spoken English, you can talk about someone giving help for doing something with this phrase. Some other examples:
Would you help me put the groceries away?
Help me lift this, would you?
When you "put something together", it means that you make something by collecting materials or information from different places.
When you use a short pronoun like "it", "they", "something", etc. it goes between "put" and "together":
We put it together quickly.
We can put something together later this week.
When you use a noun or noun phrase, it goes after "put together".