There are loads of posts about the main “No root file system is defined" problem, which say to address this by specifying ext4 as partition type "/" as mount point. HOWEVER, I've not seen anything which addresses how to do this for setups with a separate root partition.
On my 250gb SSD, which is dev/sdd/ I have:
sdd1: existing efi boot partition
sdd2：现有的xubuntu 19.10 / home安装我想用xubuntu 20.10覆盖
sdd3：Windows 10我想独自离开
BUT in the install options, I can't see how to specify that I want the boot partition to be sdd1 & the /home partition to be sdd2. Firstly it doesn't recognise the existing mount point status of sdd1, and secondly it doesn't look like I have the option of setting sdd2 as the install location but having sdd1 as the "/" mount.
也许答案很简单，但我只是保持谨慎，因为我不想做出最好的猜测并破坏任何东西，例如还必须重新安装Windows。
请有人建议如何解决此问题，即如何以与当前相同的设置安装xubuntu 20.10（即单独的启动分区）;也，
请有人考虑是否值得拥有一个单独的启动分区？在某些时候，我必须阅读有关使用它的好处的信息，尽管现在它是一个问题（尽管是次要问题）的原因。
谢谢！！
