[ubuntu] HELLLLPPP!!! Stuck in a loop at startup

**Update:
OK, so it seems it was the boot order in the legacy boot options that was set to Network before USB storage device.

But now on to the next problem...

I'm stuck in a loop.

I try to run Ubuntu Studio without installation and it just keeps restarting my computer and coming back to the same screen (boot options for Linux OS)

**Original Post:

"Hi everyone,

I used to test linux distros all the time back on an old desktop tower...
Now times have changed (a lot, even in a year..) and I have a windows 10 Dell Inspiron 5-something.

After a while of frustrations with windows (just name any problem, I have it, grhhh windows), I remembered about Linux, and so I went ahead, downloaded the OS (ubuntu studio, since I am making Audio Prod.), installed it on a partition(100GB) of my USB-HDD (Seagate 1TB).

So now I have a boot-able Ubuntu Studio USB-HDD.

The problem is when I try to run it, after getting past the BIOS/UEFI, Secure Boot options, I was able to boot from the drive but then I got this error:

"Realtek PCIe FE family controller series v1.34 (10/17/13)
PXE-E61: Media Test Failure, Check Cable" *Image of a screenshot is attached.

After a little reasearch it seems to be that it is trying to boot from network instead of the USB-HDD.
At least that's what I got online, but I have a feeling this might not be it because when I am using Windows 10, the Realtek driver ALWAYS ****s up. The sound starts to crackle and clip.

Could this be as simple as a boot order? Is it a bad cable connection? Is it because of Realtek?

Any help would be appreciated, meanwhile, I will check the bad boot order possibility.