One of the huge bugbears for students when writing essays is the whole process of in-text citation and bibliography. There are no substitutes for good old-fashioned teaching around how, and when, to use citations in text and how to go about creating a bibliography, but the collation of bibliographical information and formatting of bibliographical entries has always been problematic, for students of all ages. Thankfully there are a number of websites available, free to use, which allow you to create bibliographies with a minimum of fuss and bother. They all work in fairly similar ways, and offer similar services, usually with premium versions offering long term storage of citations, plagiarism checking and so on. It is easy enough to find a free one such as EasyBib, which you can use to generate website, book, journal and a range of other entries. Users are asked to type in the URL or title of book or journal article. The website then searches for the information and offers a suggested bibliography item. Most services allow users to add additional information not captured. You can then copy the bibliography and paste it into your essay.
To my mind the thought that students need to put into citations should be on the in-text part, rather than the formatting a bibliography part of it. Having a handy online tool liberates teacher and student to concentrate on this aspect. Most online services offer an opportunity to copy the in-text citation as well as the bibliographical entry, but I prefer to get students to do this themselves. How hard is it to extract author and date information? You also need to make sure that students are able to check what information is being generated for accuracy and update missing data where necessary. Getting students to work in pairs to do this is a good idea.
If students are using different websites, get them to rate the accuracy they achieve and make recommendations to each other.