Is it considered plagiarism if I use open educational resources (OERs) without citation?

Yes, using open educational resources (OERs) without proper citation can constitute plagiarism. Even though OERs are freely accessible, you must still provide attribution to the original creator or source
AppIy for paepr Publication https://www.edwinincorp.com/edwin-group-of-journal AppIy for book publication https://www.edwinincorp.com/edwin-group-of-publications