How do I add two different RAIDs to my Nextcloud?

Hello together, I searched for quite a while, but I could not find something about the use of two different RAIDS.

I am on the latest Ubuntu 20.04 LTS and have 5 different Harddrives in it (all connected via Sata).
One as the system drive (like in Windows the ā€œCā€ Drive)
Two 6TB drives in RAID1
Two 1TB drives in RAID1

Due to the way I have organised the data, I would prefer it to have both RAIDs accesable from the cloud.
At the moment I only get acces through FTP.

I hope someone has an idea how to solve this.