Trying to install Ubuntu on external hard drive and Grub on internal harddrive – BIOS

im trying to install ubuntu on my external hard drive and Grub on my internal hard drive, i once installed ubuntu on my internal but i dont have much space on my main SSD, i use a laptop and i decided to replace my old 500gb HDD with a 250gb SSD and i use my old one as an external disk.I already made a question asking how to install this but it was pretty bad an i didnt gave much info. After i tried to install it and rebooted my computer i got this error:

error: no such device: e5ba289-b231-4ad9-abda-b6a8a04c1c1e error: unknown file system entering rescue mode…

After i saw this i rebooted my laptop and booted my USB with ubuntu, and installed boot-repair, after another reboot i got the normal windows 10 starting screen.

I have the log from boot-repair if you need more information please leave a comment and i will give you the required information.

The boot-repair log: