Please watch the video using the link provided that will show the main issue I'm having!
Download the video if unable to watch!
Watched the linked video; In your boot order within BIOS, do you see one labeled 'Ubuntu' or 'Zorin'? I've seen the Win sys repair boot and the grub shell if the boot order gets out of whack..
Check your boot order and see what's selected for first boot 
It says Ubuntu even though it is actually Zorin but issue is I can't login to either OS!
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Login or boot? Looks like you're not booting Grub and the Win Sys Repair partition instead; neither the Win boot loader or Grub (Zorin / Ubuntu)..
Take a look through this - you have a Dell, so check the Dell BIOS settings section.. also, might not be what you need either so bare in mind - might not be the fix for you.. But, going off of the video and description, may be.. Just remember to save any settings changed! (BIOS)
Oorr - might just need to rewrite Grub as @Aravisian points out; only need the live installer for that one
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I watched the video. I would definitely begin with Grub Repair. While at it with the LiveUSB booted, check a S.M.A.R.T. test on the drives integrity, as well.
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Right now I really want to login to Windows 11 but I can't fix this issue or reset my PC!
How can I resolve this issue first of all?
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You could try to change the boot option in BIOS to 'Windows Boot Mgr' to see if you can get into Windows that way; if so, I'd say just the Grub repair is needed.. Won't curse anything and go into 'if not..' just yet 
But, that's just to get into Windows; the Grub will still need rewriting seems like, though..
The Grub menu is a separate issue.
The issue is I can't login to Windows as I needed to get back into the VM that has a Linux OS installed in it - that is the only reason I still use Windows OS.
If anybody else here ever used Windows 10/11 - pleaae watch the video I posted and tell me the solution.
The video didn't show any login prompts - just the Windows repair.. And if you got to a login prompt - did you mistakenly enter the wrong password by chance? 
..
You'll find that almost all the users here are former, or current, Windows users. Most of the common boot issues that are seen with 10 and 11 are also in as early as Win7 systems as well. The video posted does show booting to the Windows repair partition which points to a Windows loader issue. So, you might need to make a Win10/11 USB installer, run the auto boot repair stuff, maybe even get to a CMD prompt and run the bootrec commands 
without more information on what's going on than 'I can't login', it's hard to tell what you need to do.. But, from the video, and description - you need to rewrite Grub from any Linux / Ubuntu installer if dual-booting or solely using Linux / Ubuntu - Or - repair your Windows loader with an install disc or USB:
MS has a 'Media Creation Tool' on their site to use and make a bootable USB installer for free btw:
Just select what version you need.
For more info about my issue, I'm not dual booting at all instead I have 2 separate SSD installed inside my PC - 1st Slot Zorin and 2nd slot Windows 11.
I did go into my BIOS changed the boot order to start up Windows 11 as first.
When I get inside the Windows Boot Manager, I can use the command prompt but starts with the letter 'X' instead of 'C'
So, when you're booting back into Windows (changing BIOS boot order), did you re-enable secure boot within BIOS? Not necessarily needed for Linux / Ubuntu - though can be setup - but, is most definitely enabled for Windows by default.
X: and C: - X is the indication of the installer / repair drive. Just issue cd c: to change to the main C: drive of your Windows install, then enter bootrec commands like bootrec /fixmbr or bootrec /fixboot.
No I did not (nor will I) change to secure boot.
So on the command prompt I firstly enter in: CD C:
Then the bootrec commands right after?
Yes - after changing to the C: drive, then enter the bootrec commands and reboot to test. Give the auto boot-fixing option a try first though; might be able to knock it out with a few clicks instead.
Ok I just gave this a try and after entering in bootrec /fixboot, it said 'access is denied.'
Did you try the boot repair options in the Advanced menu and startup repair first before entering commands?
Also, if using the Advanced menu options and fixing startup issues doesn't work - enable secure boot and give the repair another try. But, if you reinstall Windows, secure boot will be enabled by default - just saying.. Might want to try like how it was setup OOB...
Why Secure Boot?
What effect will that have?
Have you tried the automated startup repair?? Not the installed repair tools, from the installer disc or USB.
The goal is that you may need to have the BIOS settings, including secure boot status, in the same configuration as you received it from Dell - that may be causing the 'access denied' but also has some other issues related to that that are not needed at this time.
Try the auto startup repair from the Windows installer media, if that doesn't work - turn on secure boot and try again.
I've tried enabling secure boot and then automatic startup repair and it still did not work...
I need to try something different now...
This thread has rapidly progressed.
It began with an undefined error displayed at boot, then escalated to being unable to boot any system.
The first things I would check, assuming that your attempts at Grub Repair were not fruitful, is check the integrity of the hardware. Run a S.M.A.R.T. test on the drive(s) to test for failure, bad sectors or bad blocks.
Using a LiveUSB, you can use dmidecode to check the integrity of your motherboard:
sudo dmidecode |grep -B 2 Stat
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I've just done a test on the hard drives and there is no issue detected - it is the OS that is currently the main issue!
I really am unsure of what to do next...