Windows 10: Need Help Booting from Cloned Windows 11 HDD and File Transfer Query

I'm currently facing an issue that has me stumped and in need of some guidance regarding a Windows OS cloning and booting problem.Here's the situation: I used Macrium Reflect to clone my Windows 11 operating system from my internal SSD onto an external HDD. My intention was to downgrade back to Windows 10. However, upon attempting to boot from the cloned drive, I encounter the dreaded "inaccessible boot device" error. As a result, the system automatically boots back into my original SSD, which currently runs Windows 10 after the attempted downgrade.I've tried several troubleshooting steps, i

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Failing HDD and Cloning

So if an HDD is slow(Seagate 2TB HDD) and the HDD loads really slow in windows and for scanning how long may a sector by sector cloning take if the HDD if almost all of the 2TB is used up if the cloning is done on a boot up CD?

Basically, the HDD is now painfully slow to load up in windows and takes light years to scan if it does scan.
2TB space almost used up.
It's a Seagate HDD.
Boot into CD software, not windows.
Sector by Sector cloning from there.

Also, if a Seagate software were to exist for this, would it be any faster?

Note: This drive is said to be at 4% health...

At this health, what is the likelihood of recovering all files not in bad sectors?

And what about files in bad sectors?

What is the fastest way to clone a failing HDD and is now really slow?

And what other ways are there to transfer files from this HDD myself?

 

Cloned HDD wont boot

Background: Two partitions on HDD. Bought a new HDD and this is what happened...

Program I use is Easeus disk copy. It has 2 modes to clone data. Clone disk and clone partition. Whenever I tried the option that only copied the primary/windows partition, I got an error at boot. When I did the whole HDD copy, everything worked like a charm.

No, I had no important windows files in that second partition. It only had my important files.

 

Need Help Files Transfer

I have a computer running Windows XP Home Edition. That computer has two internal HDDs:

The 1st HDD is C:\ that running Windows. And it has 20GB total of capacity.
The 2nd HDD is D:\ that is empty. And it has 90GB total of capacity.

The C:\ drive is almost run out of space (full). Is there a way I can transfer everything in the C:\ drive to the D:\ drive and begin to use the D:\ drive from there on as primary drive?
Can the Windows Files Transfer feature in XP transfer everything I have in C:\ to D:\? If it cannot, then which way can I use to perform the above step?

Thank you.