So, after ages working exclusively with Windows environment, I decide to get back and mess around in Linux systems. I opted for OpenSuse 15.3 and so far so good.
The problem is, I still need to work in Windows, but, as a good noob, I did something wrong when deciding the partitions scheme. I opted for what the installer recommended.
What I know is, I don’t know anymore what I’m doing.
My first choice would be restore the Windows boot to get back to that instalation.
Your output would have been easier to read with CODE tags.
From what I can see, “/dev/sda” is using standard DOS partitioning, and it looks as if Windows is there.
The second drive ("/dev/sdb") is using GPT partitioning and UEFI booting. However, there is something a bit unusual. You have a small 16M partition starting at sector 34. That’s uncommon, but allowed.
It looks as if Windows is on the first drive, so booting with BIOS/MBR, while linux is on the second drive and likely booting with UEFI.
I’ll suggest you go into BIOS settings, and see if you can tell the BIOS to boot the first drive with BIOS/MBR booting, The BIOS might call that CSM (Compatibility Support Module). If you can switch it to that mode, you can probably boot Windows, but perhaps you cannot boot linux unless you switch it back. I’m suggesting you test this. If that’s the issue, then you can switch linux to booting with CSM, and that will solve your problem.