Hi, I started using Ubuntu recently, have it on a SATA SSD but now have also a NVME SSD that I’d like to have OS in. I found guides showing how to set up root and home directories on two drives and that seems appealing, however I’m not sure on setting up the /home directory step as the disk already has it. Should I format this drive beforehand and do a new install? Or should I just install everything on the NVME and change the paths for file folders? Is it more difficult than installing /home on a separate disk?
Also, will I be able to install programs and games on the root drive, and do I need a ‘Swap space’?
If you have the choice to do a clean install, take it.
Swap Drives are HDD space used as additional RAM or a “safe haven” for information when your system is hibernating.
My system (A desktop) is running after a clean install using default settings and no Swap Space.
There’s still not much in it, so yeah 
Thanks for reply.
I would prefer to format and configure the already shared library for 2 hard drives. It will work much more stable this way.
Which library is shared, is it difficult to configure? Also this is one of the guides I read Installing Ubuntu with Two Hard Drives | Linux Journal So far I haven’t done anything with the NVME drive as it has yet to be formatted.
Here is what I did:
https://itsfoss.community/t/needed-windows-for-my-vehicle-diagnostic-software-update/6701
Very simple…Two independent installs, resulting in a grub menu that gives you a choice of which operating system to use. Here’s a pic of the grub menu:
So besides a / partition, an EFI partition was needed in the root drive (this was helpful Installing Ubuntu Desktop 20.04 LTS – Linux Hint). Is it correct you can’t add anything to the / partition disk? Can I create a third partition besides / and EFI for programs that can be moved around?
Partition OR disk?
You can add virtually as many partitions as you want to the disk, but not to the partition.
Partition - I can’t add new folders in it. But if I add a new partition, does it have to be of certain type or can I name it whatever and use it to store programs?