Have you an @outlook.com email address? Or a @live.co.uk? I think you probably have a free onedrive by default. It's pretty hard not to open a microsoft account now when setting up a new windows device so maybe that's where it came from. If you can unearth the email account, log in and see what happens.
I use both onedrive and google drive.The last copy of office I bought was 2010, I just have a onedrive/Microsoft365 sub now that gives me office and something like a 1TB of space. All my files are in the cloud. It's hard not to be in somebody's eco-system and I find all Apple stuff even more frustrating.
At one point I was going to bin Google and go MS but Windows Phone flopped:(