Yes, your WD My Passport has a USB port (Micro USB-B 3.2 Gen 1), you can connect it directly to the USB port of your PC. No extra connector needed, it is powered via USB and is plug-and-play compatible.
The stated read transfer rate of 5000 MB/s is incorrect for this external hard drive. In fact, this model offers sequential read speeds of around 115 MB/s thanks to its USB 3.2 Gen 1 interface, which is typical for a 2.5-inch mechanical hard drive at 5400 rpm.
Wireless? So a WLAN hard drive with an internal battery? If so, then it would probably have to be an SSD, not an HDD, for reasons of power consumption. You haven't found anything like this and I haven't come across it myself. But I could imagine that you could find something like this with an intensive search. But it's unlikely to be mass-produced and therefore not cheap.
Yes.
But: the 1TB version is formatted with NTFS for Windows and must be reformatted with HFS+ for Mac before use.
The 2TB, 4TB and 5TB versions for Mac are formatted with HFS+ by default.
Recommendation: Buy WD My Passport - for MAC (2TB). Comes with USB A and USB C cable.
Unfortunately, I can't tell you the exact differences. I would recommend BitLocker, because it is a professional solution, and WD Security for the normal end user. The only advantage I see with WD Scurity is if you also want to use the hard drive for Macs. Otherwise, as long as you have the "key", you can use the hard drive on different computers.
Yes, the WD Elements Portable 4TB hard drive runs under Windows7. It is factory formatted in the correct format (NTFS). Quick note: You asked your question under the WD My Password 4TB. This is also compatible with Windows XP or higher (also Windows 7) and is also formatted in the factory in NTFS format.
Greetings
Colin
This model is the most recent, released in 2019 compared to 2018 for the 8609359. The latter was still compatible with Windows 7, which is no longer the case for the 2019.