Journal articles are a pillar of academic research, and can inform your papers with current and relevant information. Here are recommended databases -- each containing a number of journals -- where you can search for articles on topics related to philosophy.
An archival collection of scholarly journals, ebooks and primary sources. Includes content across the disciplines, including African American Studies, Anthropology, Asian Studies, Economics, Education, Health Sciences, Humanities, History, Indigenous Studies, Literature, Mathematics, Philosophy, Political Science, Science, and Sociology.
You will often be asked to find scholarly articles for your assignments. Have a look at this Popular vs. Scholarly Articles guide, which outlines some of the differences between popular and scholarly articles.