Minecraft boots up, and then dies

Hello, I recently tried making a new mod on MCreator 2024.4, but, after I added two things (a block and a creative tab) I pressed the run button and when the Minecraft window opened, it closed right after. I searched it up, but found nothing, no solutions worked, I even tried making a new project and running Minecraft without adding anything, but that also didn't work. What do I do?