[Edited: 2 years, not 5]
Unless you have been in the US more than 5 years, As a J-1, if you have been in the US 2 years or less, you are considered a non-resident alien and file a form 1040-NR that only reports your US-source income and does not report any other world-wide income. That won't change in 2024, you will continue to file a 1040-NR and only report your US-source income. Whether you also owe tax in your home country is up to the laws of that country.
If you have been in the US more than 2 years and are considered a US-resident for tax purposes, you would be a dual-status alien for 2024. There are special rules for dual-status aliens, and special rules that apply in your exit year. Let us know if that applies to you and I will locate the best expert on that topic. But for a regular J-1 less than 2 years, your tax position won't change.
