https://www.cnet.com/news/google-io-2018-what-to-expect/

Just like last year it will take place at Shoreline Amphitheater in Mountain View, California, and we'll hear what Google has planned for developers as well as what new products and services we can expect over the course of the coming year. While there's always room for surprises, we have a pretty good idea what we're going to see on stage at the Shoreline at this year's I/O. 

Since we already saw the first preview for Android's latest mobile operating system earlier this year, an Android P announcement at Google I/O is at this point a foregone conclusion. The second developer preview will likely be announced on Tuesday, and we have a pretty good idea what will be shown, but also know that new changes might be announced on stage.