Hi and Welcome Dave!
Linux and Windows desktop systems share a common problem: they are one-size-fits-all. This means that with every passing year the task of making your code run on everything becomes a harder and harder. The blunt fact is that some software simply won’t run on some machines. For example, I have two old laptops which are the same make and model but that were built at different points in time. Google Earth runs on one but not the other. This turns out to be the result swapping out components during manufacture due to supply chain issues.
So It’s quite possible Wine 5.x simply can’t run on your machine. You could have an unusual hardware config, for example. Also, Mint is an extremely conservative about the software will support because it values stability above all else. That it tries to install 3.6 instead indicates that it is one or the other.
Two OS’s that might easily run wine 5.x are Arch (because of its “hackability”) and Zorin (because ships with highly developed Wine builds).
When I ran Zorin for several years I could easily get a lot of old Windows software to run. When I switched to Mint it all became a pain. So distros do matter. And when for a while several years ago I absolutely had to run ms office, I ended up saving a old Zorin partition just to run Wine.
Finally, a mechanic friend of mine often says: “Never the first year of anything unless you’re looking for a new hobby”.