Creating non root users that can ssh into debian system to SFTP raid controller config file for bios upgrade

I'm new to OMV but have wanted a NAS for some time. I have repurposed a HP ZX8600 dual xeon ws with 24g of ddr2 ram, 128g SSD (SATA) for the OS and 3 seagate constellation 4 Tb enterprise drives for storage I had to add a PCIe raid controller to use the SAS drives HP P420. I installed mergerFS and snap raid. On my first try the raid bios setup utility forced me to create a logical drive containing all 3 data drives, but then I had to use the hardware controller to manage the raid configuration. This made snapraid pointless, so after some research I rebuilt and set up 3 separate logical drive and was able to setup mergerFS and snap raid. Only downside is that SMART can't monitor the logical drives. More research and HP has a BIOS upgrade for the P420 controller that allow it to function as a RAID controller or a HDA controller that would allow me to setup the 3 data drives as JABOD array and I think then the SMART utility will be able monitor them correctly. All this to say that the only user that was created by the OMV install that can access the server with WinSCP or PuTTy is root. I've tried creating a user through OMV and the adding them to the ssh, sys and sudo groups and they can't access the server. It connects but access is denied. so I deleted those users and use the root login to connect using PuTTy and created the users through the command line modified them to be in ssh, sys, and sudo groups but they still can't log in. I'd really like a user that is not root to be able to use the command line in debian if I need to, but after several hours of troubleshooting I'm not any closer

actually I misspoke I did add user to _ssh group there still seems to be an issue with the <user:user> group not existing

I fixed it by trial and error thanks