Repair MBR or GPT Table from recovery as both OSs fail to boot

Question

On my Mac Mini 2014 I tried to repair GPT table (MBR.. ?) with an answer given on Trying to rebuild my partition map (using GPT fdisk, SIP disabled) for my issue of Windows 10 not booting itself but by going through the Option menu on each boot. And, it's messed up now.

I can't boot to any of the OS now. I even can't reinstall the MacOS. I have tried to take screenshots of the output with the reference of the thread. Please help me to recover my OSs.

HUM

New screenshots:

1. DiskUtil

Additional information:

Hums-Mac-mini:~ humgurung$ ls /Volumes/BOOTCAMP/boot/bcd
ls: /Volumes/BOOTCAMP/boot/bcd: No such file or directory
Hums-Mac-mini:~ humgurung$ sudo diskutil mount disk0s1
Volume EFI on disk0s1 mounted
Hums-Mac-mini:~ humgurung$ ls /Volumes/EFI/EFI/Microsoft/Boot/bcd
ls: /Volumes/EFI/EFI/Microsoft/Boot/bcd: No such file or directory
Hums-Mac-mini:~ humgurung$ diskutil unmount disk0s1
Volume EFI on disk0s1 unmounted
Hums-Mac-mini:~ humgurung$ sudo fdisk /dev/disk0
Password:
Disk: /dev/disk0    geometry: 60801/255/63 [976773168 sectors]
Signature: 0xAA55
         Starting       Ending
#: id  cyl  hd sec -  cyl  hd sec [     start -       size]
1: EE    0   0   2 -   25 127  14 [         1 -     409639] <Unknown ID>
 2: AF   25 127  15 - 1023 254  63 [    409640 -  195312496] HFS+

*3: F7 1023 254  63 - 1023 254  63 [ 195723264 -  781049856] <Unknown ID>
 4: 00    0   0   0 -    0   0   0 [         0 -          0] unused

Hums-Mac-mini:~ humgurung$

UPDATE 2 RESULT:

Answer 1

This answer is only intended make macOS bootable. There may be further repairs which need to be made.

You should be able to use the following command to make macOS bootable.

fdisk -e /dev/disk0

This command is interactive. Enter the values in the order given in the first column of the table below.

Entry	Type	Comment
e 4	command	Edit given table entry 4
0	parameter	Partition id ('0' to disable)
q	command	Quit edit of current MBR, saving current changes

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Update 1:

If the Boot Camp Assistant is used to install Windows 10 on your 2014 Mac, Windows 10 is installed to UEFI boot. From what you have posted so far, it would appear Windows 10 is installed to BIOS boot. This could happen if you upgraded from a previous Windows install (such as Windows 7). The existence of a BCD file in the /Volumes/BOOTCAMP/boot folder would indicate BIOS booting. In other words, the output from the command below can be used to help determined is Windows BIOS boots.

ls /Volumes/BOOTCAMP/boot/bcd

The existence of a BCD file in the /Volumes/EFI/EFI/Microsoft/Boot folder would indicate UEFI booting. In other words, the output from the commands below can be used to help determined is Windows UEFI boots.

sudo diskutil mount disk0s1
ls /Volumes/EFI/EFI/Microsoft/Boot/bcd
diskutil unmount disk0s1

Could you enter the above commands while booted to macOS and post the output?

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Update 2:

The id the MBR table for the third partition should be 07. This can be changed by entering the following command while booted to recovery mode.

fdisk -e /dev/disk0

The interactive entries can be taken from the first column of the table below.

Entry	Type	Comment
s 3	command	Set the identifier of table entry 3
7	parameter	Partition id
q	command	Quit edit of current MBR, saving current changes
y	parameter	(Optional) Enter if asked for OK

Note: In the MBR table, the id of the second partition currently is AF, which represents a HFS+ type partition. Actually, your second partition is APFS, but since there is no official id assigned to APFS, you might as well leave the id as AF.