Halo Infinite was slated to be released in fall 2020 alongside the launch of the Xbox Series X|S. According to the game developer 343 Industries, Halo Infinite will now be released in fall 2021.
“After Reach shipped, I became a Halo fan, cheering-on 343i from the sidelines. But I’ve spent the last four months immersing myself back into the Halo universe, and it’s my honor as creative director to help our team ship Halo Infinite in Fall 2021” – Joseph Staten, creative director of Halo Infinite
source https://www.simpleprunes.com/2020/12/halo-infinite-is-coming-to-xbox-series.html