Scholarly articles are papers written by (usually multiple) experts in a subject and published in academic journals. The experts submit the papers they have written to be published in academic journals. These papers focus on specific topics and may be written about new research studies, case studies, reviews of previous research, or other research-related topics.
Academic journals are run by editors and published by publishing companies, universities, or professional associations. Most academic journals use a peer-review process to review articles for quality. Most academic journals have scopes, and they only publish articles that fit within the journal's scope. An academic journal that doesn't have a peer-review review process or has a very broad scope has warning signs of being low-quality.
A database is a collection of many different academic journals that can all be searched at once. Databases allow you to limit your search by certain filters, usually including by peer-review status. You can filter out likely lower quality research.
You can search a database by creating and submitting a search query. Based off your search query, you will get a list of articles (and other resources) as results.