There are a few exceptions to this general rule. For example, students with disabilities that make it difficult or impossible for them to fill out their own applications may be able to have someone else do it for them. In these cases, it is important to disclose this information to the admissions committee so that they can make accommodations.
Another exception may be if you are working with a college admissions consultant. College admissions consultants can help students with the application process, but they should not be filling out the applications themselves. Instead, they should provide guidance and support as you complete the applications yourself.
Ultimately, the decision of whether or not to have someone else fill out your college applications is a personal one. However, it is important to weigh the ethical implications of this decision before making a choice.