The article is talking about the federal fiscal year that started on Oct 1, 2024. Biden is responsible for Oct-Jan, so 5 of the 10 months.
Maybe the chart of the monthly deficits on this page will help you understand the change in direction of the deficits since Trump took over. While not on this chart yet, the July deficit (like June) will be in between 2023 and 2024.
https://bipartisanpolicy.org/report/deficit-tracker/
Biden, or whoever the hell was running the country then, was a complete deficit disaster the first 5 months of the current federal fiscal year. You can already see Trump changing the course in just a few short months. Yes it could and should be better, but there's a lot of f*ck ups to fix from Team Autopen Biden.