I have been using Linux installed on an external hard drive (lets say A) for a year, so everytime my hard drive was connected i could use linux and when it wasnt i could use windows.
Now i have taken another external hard drive(lets say B) and i did the same proccess to install linux.
What i wanted to do was to be able to use both of the external hard drives( A and B) and the internal hard drive that had Windows Unfortunately, when i installed linux on drive B i used as mount point the "/" that was the same i used for drive A
As a result i can now use drive B and internal hard drive but not drive A because the system doesnt find it when booting. When i am using drive B, when i plug in drive A i am able to see the files but not use it as an OS
My question is, can i change the mounting point of drive A since i can not enter it as an OS without loosing the files that are in it, so than when booting i can choose if i want to use drive A,B or internal hard drive?
EDIT: Is Windows in the internal drive running in UEFI mode? Yes Did you install Ubuntu in the external drives in UEFI mode? Yes Did you create separate EFI System Partitions (ESP) in each of the two external drives A and B? I am not sure, I followed exactly this tutorial : https://www.youtube.com/watch?v=YIhYitXwJfE
EDIT2: The pictures from Gparted are here https://i.sstatic.net/8kYwp.jpg The first one(with 930.4 Gib) is the external drive B:
and the second is external drive A(the one that i cant enter):
As I said, i cant boot from external drive A, only from B or internal drive.
The page i see when i plug in external drive B is almost like the third picture i found online:
The only difference is that it has the option "Windows boot manager" below the option ubuntu.
What if i change the mount point of drive A to "/"? Will I have problem with drive B?


