How can I Screen Share into Ubuntu remotely after a fresh boot?

I usually use Ubuntu via Screen Share (RDP) in another building and sometimes I need to reboot. But 1st thing after a reboot is a box asking to authorise the keychain/keyring which I can't type into remotely. I do not wish to root/sudo the whole OS in order to get around this as others have suggested. As another example, I also use my iMac remotely via Screen Share in a similar fashion. If I reboot the machine, I can still Screenshare into the login screen and type my password after a reboot. There is no need to disable any passwords or security features. So how can I reboot a Screen Shared Ubuntu OS and get to the desktop again If I can't physically type things into the keyboard?