Writing at university may involve researching the ideas of other people, which you can combine with your own ideas and conclusions. Learning to acknowledge other people through in-text citing or footnotes in addition to providing a reference list will help differentiate between their ideas and your own.
This is central to the idea of academic honesty in Western academic institutions.
So why reference?
Read the VU Academic Integrity and Preventing Plagiarism Policy for more details.
A basic reference list entry for a journal article in APA must include:
Example: Ruxton, C. (2016). Tea: Hydration and other health benefits. Primary Health Care, 26(8), 34-42.