Even then I had go through additional steps outlined after "If bootrec utility doesn’t fix it..."
After that, I had to change boot priority in BIOS to get to Ubuntu (because after following the steps in the link I provided it defaulted it to Windows) and in Ubuntu, I ran the commands that M.Yurizaki mentioned sudo os-proberandsudo update-grub. It detected Windows right away and I am now able to double boot.
Thanks, M.Yurizaki and Lukyp for your help.
What a relief, I came very close to reinstalling Windows entirely.