Just like Titanfall 2, then.
Infinity Ward have never exactly gone out of their way to court the PC audience- in fact, famously, they refused to have dedicated servers in Modern Warfare 2 on the PC, leading to widespread outrage, and maybe indirectly causing the decline of the franchise on PC. And while since then, other Call of Duty developers, most notably Treyarch with their Black Ops games, have attempted to make amends, it seems like Infinity Ward are not exactly interested in meeting PC gamers halfway.
What else can explain their refusal to have any beta for Infinite Warfare, which launches later this year, on PC? Especially considering the negative reception that Infinite Warfare has received so far, and that Black Ops 3 had a very successful beta on PC last year, it makes no sense to not have a beta for the game on PC, too. It’s basically them ceding the market to Battlefield 1 this year, since most PC gamers won’t get a chance to reverse their negative perceptions of the game so far.
That said, if you own a PS4 or an Xbox One, you’re at least getting beta access- make sure to register for it on the official beta registration site. Call of Duty: Infinite Warfare will launch on PS4, Xbox One, and PC on November 4, 2016.