I don’t know what i need update for 8, 8.5 or 9 I bought 8.5

and i get free update 9 service

I want to update 10

what is choice to update???

8.5 or 9 ???

I don’t know

What matters is the license on the USB-eLicenser. If a Cubase 9 license is listed in the eLicenser Control Center, then you would have to update from version 9. If it is 8.5, then that is the correct version.