BootDevice Not Found - acer aspire s7

[Şerban S.]

And about GPartEd, the screenshots just below :

https://ibb.co/56V9tzM
https://ibb.co/318J59h
https://ibb.co/7CpRFqS
https://ibb.co/LQVW4KJ

I hope it's helpful

Thanks again for your time

First two screenshots, show you the real physical drives. Since they are in RAID mode, they are unusable. "Busy", so to speak.
The next two drives, are logical, since this is the way RAID works.
Now, you need to create a partition table. You can use GPT, since the machine is with UEFI firmware.
After creating the Partition  table, you can create at least a FAT32 partition of 512 MB and an ext4 partition.
After creating the /dev/sdb1, change its type flag to "boot, esp".
After that, you should be able to install Linux Lite on the newly created partition (/dev/sdb2).
Before pressing the "Install now" button, be sure to check the place where the boot loader will be installed.
The name has to be the same as in GPartEd screenshots. In this example, should be  /dev/sdb1, since this is where GRUB has to go.
You should see something like:
/dev/sdb1, FAT32, 512 MB
/dev/sdb2 ext4 , 128 GB (or so)
After installing Linux on /dev/sdb, you may partition the other logical drive (/dev/sdc) from within Linux Lite.
Use the default install scenario and see if it finishes the install.
It will erase the partition /dev/sdb2 and create all things needed, including the SWAP.

Good luck!