This tweet was the best format for it, but here's the official site for the prize pool: https://www.dota2.com/international/battlepass
I expect this will easily break $35 million USD by the end of it. The International was supposed to have happened last week in Stockholm, but it got delayed to an undetermined time due to COVID. The prize pool is still going since the Battle Pass ends in mid September.
25% of proceeds from Battle Pass and levels for it contribute to the prize pool. Also since it broke last year, everyone that owns Battle Pass gets an extra 10 levels!