Windows 10 Windows can's boot after Ubuntu install

Hi again Kevin,
I agree with Mike here. Unless your Motherboard is bad, the reinstall of W10 on your bootdrive hard drive should work 100% of the time. Re-reading all the posts in this thread again, you haven't answered us on all the things I suggested you try back in my Post #7. The 2 key things you need to do to get your computer going again are: (1.) Remove your 2nd hard drive from the installation process, and (2.) Remove the SSD bootdrive and replace it with a brand new drive, either SSD or HDD-mechanical. With the multiple formatting of the partitions and drives you did, it's VERY likely you have messed things up on 1 or both drives beyond repair (especially when you formatted with the FAT (FAT-16) format. Modern drives today, especially SSD drives do not like that and it's often destructive.

You also didn't report back whether or not you tested that SSD drive with the link to hardware testing containing links to proper diagnostics to test SSD drives specifically. You also completely skipped the test of your RAM sticks. That can produce all kinds of installation in Windows of any version including W10 if there are failures. You need to run the MEMTEST as instructed for a minimum of 8 passes and post back the result of BOTH tests. Without you completing Hardware testing, we could go round and round for the rest of the year and never pinpoint your problem.

On the data recovery track, it's important too, that if you are a novice to data recovery, throwing all sorts of data recovery tools at your problem will most likely be counterproductive, in fact from our experience with many many users over the years it's more likely for you to lose any data on that SSD drive than to get it back. Your chances at winning the State lottery are better than you getting 99% of your data back when you have little or no experience in this area. I've been doing Data Recovery for over 30 years; and it's not something you learn in a few weeks! I already recommended to you that you Pull that drive out of your computer, and replace it with a brand new drive and then attempt a straight W10 install. You chose not to do this. Assuming that your RAM sticks are all healthy and passed the MEMTEST diagnostic, and that you are using known good W10 install media, as Mike said, 99.5% of the time, W10 should install on that brand new bootdrive. Period. If it doesn't, then most likely you have suffered a coincidental hardware failure in your Motherboard and that's a very expensive replacement; $175-$1,500. In most cases, it's cheaper to replace the entire PC.

This is really very simple, and I'll say it again NO SOFTWARE ON THE PLANET CAN FIX BROKEN HARDWARE!!!
Continuing to attempt further repairs on that broken SSD drive(you broke it when you formatted it with FAT format); is not going to get you anywhere with W10 or Ubuntu, let alone try to force it to work at this point when you still have unrecovered data on that drive!!
Hey, this is your computer and you can do whatever you want, but if you ignore these suggestions you are going to be in a world of hurt with both your data and trying to run a PC that's suffered some kind of hardware failure or failures. We're just trying to help you sort all of this out. You should also consider that between the people here that are trying to help you we have hundreds of Man-Years of experience doing this professionally to earn a living. You've now got all the information you need to solve this problem, if you are willing to follow our instructions. All of them.

Post back the results of your hardware testing if you don't mind, and then we can explore more Data Recovery options with you to get your stuff of that broken SSD drive.

Let us know how it goes.
BBJ