Bond Issuance question - UST

Hi,

I’m trying to learn more about US Treasury bills/bonds issuances and refunding.. I know the reason bills/bonds are issued but what can I read to figure out how much of it is going to be issued and why in that allocation schedule? Why a certain amount of bills or bonds? - if the treasury needs to raise 2B (hypothetical) how much of it will be in bills and how much will it be in bonds? Why those maturities?

Before you say the issuance is announced ahead of time, I’m aware of that. Ultimately, after understanding the aforementioned things, I’m trying to figure out is if there is a way to forecast it..

Any good white paper, books? Anything will help..