Both Individualized Education Programs (IEPs) and 504 plans can offer formal help for K–12 students who are struggling in school. They’re similar in some ways but very different in others. This comparison from Understood.org can help you understand the key differences between the two.
IDEA, Section 504, and the ADA: Which laws do what? https://www.understood.org/en/articles/at-a-glance-which-laws-do-what