unconstructable13 boot into ubuntu USB, click Try Ubuntu, and then try running ls /boot/efi/EFI
if you see “ubuntu”, “debian”, “Linux” or “GRUB” in that folder, then you do indeed have the ubuntu bootloader, but it’s not showing in the bootloader. try running
sudo apt install efibootmgr
efibootmgr -c -d /dev/sdb -p 1 -L "Ubuntu" -l '\EFI\ubuntu\grubx64.efi'
change /dev/sdb to /dev/nvme0n1p1 if you use an NVME drive (which im guessing not as your bios references HDDs multiple times, but you can check by running ls /dev/nvme* and then ls /dev/sd*)
change Ubuntu following EFI\ to the folder name you found
