Gmail & Cal Forwarding Support(Vietnamese) -- 2

I have several Google Accounts with email addresses and calendars. My goal is to have a single inbox and cal which all address are forwarded to. I'd also like to be able to Send As each of those accounts from a single inbox. A couple wires are currently tangled and I'd like to have a walk thru troubleshooting with you. I'm quite tech-savvy, but this is breaking my brain.