For making audio CDs, best to export your recordings as standard (16-bit stereo, 44100 Hz) WAV files. Audacity uses these settings by default when you select “File menu > Export > Export as WAV”.
Some CD players can also play “MP3 CDs”, which are “data CDs” containing MP3 files. You can get more MP3 tracks on a data CD than you can audio tracks on an “audio CD”, but many CD players cannot play data CDs.
For compatibility with most CD players, you must select “audio CD” as the CD format in your CD burning software.
One of these type of things?
If so, they are easy to use when they work, but have a terrible reputation for not lasting very long before becoming a paperweight. Keep your receipt.
They also tend to come with obsolete versions of Audacity.
So long as the device actually works, then yes it will work with any version of Audacity.
We no longer support Windows 7 (it became officially obsolete last year), but if you want to use Audacity on a Windows 7 machine, then Audacity 2.4.2 is probably your best option. You can get it here: Old Audacity versions download
Note that with the update from Audacity 2.x to Audacity 3.x, the project format changed. Audacity 3.x can open projects created with Audacity 2.x, but the old 2.x cannot open projects created with the new 3.x.
If you are only going to use Audacity on the Windows 10 machine, then I’d recommend Audacity 3.0.2 (the current version) which is available from the main Audacity website: Audacity ® | Downloads
We’re hoping to release Audacity 3.0.3 soon, so keep an eye out for that - it will have some important bug fixes.
If you intend to use Windows 7 and Windows 10, then I’d recommend the older Audacity 2.4.2, but consider retiring your Windows 7 machines soon
There’s a collection of detailed tutorials about transferring cassette / vinyl to CD here: Tutorial - Copying tapes, LPs or MiniDiscs to CD - Audacity Manual