Installed Grub on a sperate drive now my Windows 10 only boots to startup repair

[bowiye]

Windows boots from UEFI but still just into startup repair, this only began when i installed ubuntu, could it have broken my bootloader, is there a way to fix it?
I have read elsewhere of Windows having the startup repair on a different petitiion to the main OS and the boot loader just pointing to the wrong pettition although i couldnt see a way to check this myself, does this sound like a possibility and any idea how to check for this error?

I am yet to run boot-repair, if this is a tool you have worked with before or understand the options for, can you let me know if there is a fix here that i can easily utilise?

[tea for one]

Before attempting any repair, ensure that you have backups.

Windows boots from UEFI but still just into startup repair

Boot-repair is not designed to fix Windows boot problems.
You'll need a Windows ISO on a USB - it has various repair facilities and there are many helpful internet resources available.

this only began when i installed ubuntu, could it have broken my bootloader, is there a way to fix it?

Did you try any repairs offered by boot-repair?
If you only allowed it to produce a report, then it would not "break" anything.

Windows OS was a clean install when the machine was built

Therefore, disk nvme1n1 would contain an ESP, but your ESP is on another disk?
Assuming Windows 10 is located on nvme1n1p2, you should not have the following line:-
Line 6 - Windows is installed in the MBR of /dev/nvme1n1
The efi files for Windows are on sda1 (see lines 35 and 36)

It's worth the effort to try and repair Windows 10 with Microsoft tools.
Hopefully, it is successful.
Again, please don't do anything without backups.

[yancek]

I would also suggest you use windows tools to repair whatever problem you have with booting windows. There are some strange things with your setup, particularly having the EFI partition on a separate hard drive, very unusual. Boot repair usually shows the boot file on the primary windows system partition, your output does not. If your windows boot files located on the system partition are corrupted or missing, there is no way for boot repair to help with that as generally all it does is create an entry in the boot menu to chainload the windows boot files.

[oldfred]

Boot-Repair report almost always shows this:
sudo efibootmgr -v

You should have at least two entries one for Windows & one for Ubuntu that use partUUID of ESP - efi system patition.
Your line 212 in report shows partuuid of ESP.
Or to see partuuid & other partition info:
lsblk -e 7 -o name,fstype,size,fsused,label,partlabel,mountpoint ,uuid,partuuid