New to Linux and really struggling with LinuxCNC

My first post here so all my ignorance will be on display.
I'm building a CNC router and LinuxCNC is the recommended control software.
I am am brand new to Linux and having a heck of a time trying to figure out how to install it on Ubuntu 20.
Is there a place I can get instructions that are written for a complete noob such as myself?
I did search the forum but came up empty-handed and overwhelmed.

I wouldn't try with Ubuntu 20.

Mint 19.3 is a pretty easy choice. Tommy has done a pretty good write up.
forum.linuxcnc.org/9-installing-linuxcnc...nd-easy-installation

Is there any reason you didn't install from the official ISO as this is the easiest option for newcomers to Linux.

Docs are here: linuxcnc.org/docs/2.8/html/

Latest ISOs are here: linuxcnc.org/downloads/

Are you planning to use the Parallel Port or a Mesa card.
Be warned that USB is not an option as a control option for Linuxcnc.
99.999999% of any motion control cards designed for Mach3 or 4 can not be used with Linuxcnc whether ethernet or USB.
Neither can Linuxcnc talk to grbl boards.

I tried the official ISO and kept getting an error code that the g2ldr.mbr file was missing. Eventually I gave up and just installed Ubuntu.
I'm planning to use a parallel port on a desktop machine.

Hmmm that's strange.

Which ISO did you try, at what stage were you getting this error ?

IS your machine a UEFI boot only, or UEFI & Legacy boot or BIOS (legacy) boot machine. If you don't know it would be great if you can provided as much info as possible.

I got the error when the machine was trying to boot from the USB. The install stopped and the only choice was to boot back to Windows.
My machine is UEFI boot only.

Which ISO did you download & try to boot from ?

This one:
www.linuxcnc.org/iso/linuxcnc-2.8.0-buster.iso

Did you check the md5sum to ensure the download was correct ?

The Buster ISO has been used many times without issues by many users.

What did you use to write the USB stick ?

This the best utility to use:
sourceforge.net/projects/win32diskimager/

I used rufus which has a built in md5sum checker. Didn't show any issues.
I'll try again and see what I come up with.

I had another go at installing on the computer I plan to use, a Dell Optiplex 790.
When the installer got to the partition stage it went into a loop because it wouldn't overwrite the existing partition.
I had to go into the console and use fdisk to delete the partitions to get around it.
Some investigation shows this to be a known issue on some Dell machines.