Hmmm, not what I was told.
Well, if someone told you "Don't worry, you can just run all your old software on this new Linux OS!" then they were misguided; you
can get
most of it to work if you are
very persistent (Wine, the Windows Emulator, has come on a long way in the last 20 years).
If they meant "You can open all your old files [in new software]" then they were right - Linux will read all Windows drive formats and there is software out there to open
most files created under Windows; e.g. LibreOffice for Microsoft Office docs, Gimp if you're used to Photoshop, etc. (That's the GNU Image Manipulation Program, not the masks..)
This is only what I've done for a job since the mid 90s
Linux on the desktop has come on immensely even in the last 10 years - Linux Mint or Ubuntu are great easy-to-use out-of-the-box distributions and support almost all modern hardware (and the hardware they don't support, the users of this forum are unlikely to have, IMHO, with the exception of maybe TB, Rods, Kevin etc), but it means learning a new way to do everything. I wouldn't recommend it for my (75 year old) mum, my (71 year old) dad would probably figure it out and my (30-something) girlfriend gets on fine with Mint on her laptop.. YMMV.
(It's a very different world in Server-land where, as Rods describes, most configuration is done at the CLI, you don't have a GUI and you'll feel like you've just stepped back in time to the 1980s - because in some ways, you have
)
BTW, it's happy birthday to the IBM PC today - 37 years since the launch of the IBM 5150, today:
https://techcrunch.com/2016/08/12/ibm-for-president/