64bit message

With the next iteration of macOS (10.15) Apple will be removing 32bit application support. If you wish to continue using whatever 32 bit software is throwing this message now you'll need to see if the developer plans on offering a 64 bit version of their software for 10.15 or you'll need to stay below 10.15 if the software is needed.

The conversion is entirely up to the developer.

see this link:

https://support.apple.com/en-us/HT208436

You may have a partial 64-bit application solution where internal components of the application may remain 32-bit. See the vendor for an available, complete 64-bit update.

you'd have to ask the developers of wine.

You can try the demo for crossover and see if it's a possible solution.

another option is use bootcamp and run windows natively.

https://www.codeweavers.com/products

What Jimmy CMPIT said. I don't use Wine/Wine skin, and usually the developers of those products provide a list of the applications that they have tested against their version of Wine. So an update to Wine could break your old Windows application, just as an update/upgrade to macOS could break Wine.

If you mention that old Windows program, we may be able to recommend comparable functionality in a supported, macOS application.

can you cold boot to the EFI boot screen and see the WIndows 7 Partition?

I don't know if this is possible with Virtual box, I stuck a 1660ti in my mac pro and I'm running windows for 3d work but side benefit is Skyrim on ultra does not so much as hiccup.