upgrade ubuntu with dual boot windows 10 on seperate drives

  I want to upgrade Ubuntu 16 to 22. Right now I have a dual boot configuration with windows 10. Windows and Ubuntu exist on 2 separate but identical 1 T hard drives. Windows is on disk 0, Linux is on disk1 according to Windows disk management. I could post a screen shot if you need it. Windows Power Shell has this to say:

Windows PowerShell
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PS C:\Users\sam> Get-Disk
Number Friendly Name Serial Number HealthStatus OperationalStatus Total Size Partition
                                                                                                             Style
------ ------------- ------------- ------------ ----------------- ---------- ----------
0 TOSHIBA HD... 27C123LFS Healthy Online 931.51 GB MBR
1 TOSHIBA HD... 96DG88YFS Healthy Online 931.51 GB GPT

  I found the following commands looking on the web to identify the drive that is booting:

sam@Ubuntu-18:~$ lsblk -no pkname $(findmnt -n / | awk '{ print $2 }')
sdb
sam@Ubuntu-18:~$ awk '$2 == "/"' /proc/self/mounts
/dev/sdb2 / ext4 rw,relatime,errors=remount-ro,data=ordered 0 0

 <<<<< I looked in the Bios but couldn't tell which drive I'm actually booting from since they are identical. >>>>>>

I also did these commands from the terminal:

sam@Ubuntu-18:~$ sudo fdisk -l
[sudo] password for sam:
Disk /dev/sda: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: dos
Disk identifier: 0x779febc8

Device Boot Start End Sectors Size Id Type
/dev/sda1 * 2048 1026047 1024000 500M 7 HPFS/NTFS/exFAT
/dev/sda2 1026048 1952553912 1951527865 930.6G 7 HPFS/NTFS/exFAT
/dev/sda3 1952555008 1953519615 964608 471M 27 Hidden NTFS WinRE

Disk /dev/sdb: 931.5 GiB, 1000204886016 bytes, 1953525168 sectors
Units: sectors of 1 * 512 = 512 bytes
Sector size (logical/physical): 512 bytes / 4096 bytes
I/O size (minimum/optimal): 4096 bytes / 4096 bytes
Disklabel type: gpt
Disk identifier: BD275893-BB6B-44A6-8138-794C943613CD

Device Start End Sectors Size Type
/dev/sdb1 2048 4095 2048 1M BIOS boot
/dev/sdb2 4096 1953523711 1953519616 931.5G Linux filesystem

  I think the boot flag for sda is the Windows 10 boot files but the system is actually booting from the 1 meg partition at the beginning of sdb. When I installed these opr systems I did it by unplugging and re-plugging drives as I installed W10 and Ubuntu. I think I had to update-grub and maybe switch sata cables and/or the hard drive boot order in bios to get it to work as it does. It was
a while ago so I don't remember what I was thinking when I did all this :( .... I'm thinking I should make sdb unallocated space from
Windows 10 or Gparted and then boot the machine from the Ubuntu DVD. {first I may use that disk in LIVE mode to be sure it's ok}

  At last my question(s):
Will the "install alongside" option be smart enough to put everything where it needs to be.
Will the machine still boot from sdb1 and just point to sda when it boots W10 like I think it is now.
Windows is telling me I can't upgrade to W11, I think because of choices I made during the original W10 install. I want it left that way because I don't want that "upgrade".

I hope I explained everything ok, thanks in advance