MyEBSCO is entirely separate to your normal Library account in the Library Catalogue.
This is the name EBSCO - the company that provides what we call "Articles and More" (brandname: EBSCO Discovery Service or EDS) - uses for an account to save items like articles or whole searches to retrieve later, or set up alerts. This is the same account that is used for their other products like the databases PsycInfo, CINAHL, Academic Search Complete and another 21 other databases we have as a subscription. If you use one of those you may already have a MyEBSCO account!
You need to create an account to use these features; this can be done with any email address or by associating an existing Google account. You do *not* need to do this unless you want to use these advanced features. Your data will be held according to EBSCO's terms and conditions rather than the Library's.