How does money grow using agency bonds?

i’m researching agency bonds and i have a few questions:

How does money grow using agency bonds?
What are the advantages and disadvantages of this option?
what are the risks vs. rewards for this?
where do you begin investing? who does the money go to?
how much money to you need to invest to get started?
what is the minimum amount of money you have to invest and what is the recommended for the best results?
what will you need to do to monitor your investment? how often do you receive updates? what resources do you need to use to keep up your investments?

remember, all these questions should portray to Agency Bonds.