I don't understand anything

hello, I would like to know the difference between my wireless passport and my wireless pro passport, I have to buy one but I do not understand the difference.

Basically, the My Passport Wireless (MPW) is the original design model of quite a few years ago (2014) and apparently has been discontinued by WD in favor of two other later models. One was the the My Passport Wireless PRO (MPWP) with many new features. The latest today was introduced in early 2018 and is called the My Passport Wireless SSD. Unlike the previous two, it has a solid state drive instead of a traditional hard drive. It is also quite pricey. The best bang for buck today is the .MPWP in various storage capacities and prices.

BTW, why do you say you HAVE to buy one?

See this WD product page to see your two choices today.