If you want to restore your data, then start by trying to restore the data partitions, not by taking a detour somewhere else. Recovering the EFI partitions will not help you with recovering data partitions – more likely it will only be harmful, in case the process ends up creating a new EFI partition right on top of where data was.
Deleted partitions can be re-created as long as the new partition has exactly the same start sector (and as long as the tool doesn't "helpfully" erase contents). The testdisk Linux tool can be used to scan for deleted partitions.
To make the disk bootable, you'll first need to manually create and format the EFI partition using GParted or diskpart; then it can be filled in with files using bcdboot (from the Shift-F10 console), which will copy the original bootloader files from \Windows\Boot and will generate a new BCD config. See official Microsoft docs.
The MSR partition is meaningless; you can also create it using diskpart but it only exists to reserve space and not to store anything. [Not to be confused with the "System Reserved" partition of similar name that Windows uses on BIOS disks!]
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C:\> diskpart
DISKPART> sel disk ...
Create the EFI partition (efi makes DISKPART automatically set the correct GPT type guid):
create partition efi size=100
format quick fs=fat32 label="System"
assign letter="S"
Create the MSR partition if you want:
create partition msr size=16
Assuming the system disk is accessible at C:\Windows:
bcdboot c:\windows /s S: /f UEFI /v
/s S: tells it to specifically use the recently created partition instead of guessing; and since I don't trust "Tiny10" to properly boot in UEFI mode, /f UEFI tells bcdboot to specifically copy the EFI files even if that's not what the installer is booted through.
The procedure is almost the same for BIOS (legacy) boot as well – except instead of "EFI System" FAT32 partition you have a "Microsoft System" NTFS partition, and the DISKPART commands are slightly different, but it is still populated using the same bcdboot (/f BIOS) in the end. See Microsoft docs.
Create the system partition:
create partition primary size=100
format quick fs=ntfs label="System"
assign letter="S"
active
There is no MSR partition on BIOS/MBR disks.
Use bcdboot with /f BIOS.
(There would be an additional "boot sector" step when starting from a clean disk, but the MBR boot sector was not deleted – it exists outside of any partition – so you probably don't need to reinstall it.)
