No... Arraignment is your first court appearance in front of a judge where charges against you are formally pronounced. It can be proceeded by a bond hearing in some states, but most have the bond hearing in the same arraignment hearing.
Until then you are “arrested and being held on suspicion of” a crime pending formal charges brought by the DA which has to happen within 72 hours or they have to release you before the bond/arraignment hearing.
https://www.findlaw.com/criminal/criminal-procedure/arraignment.html
Yes, and your arraignment is when they have to inform you of your charges.
“Still, there is no general requirement that, at the time of arrest, an officer has to share this probable cause assessment with the arrestee.”
https://www.findlaw.com/legalblogs/criminal-defense/do-police-have-to-inform-you-of-your-charges/
The police can arrest you and try to question you, all without you knowing why. Of course, you can enact the Fifth Amendment, but this is what the police are allowed to do.