How do I add filters to website API?

You can add filters to your site manually, but it is time-taking and technical. If you don't want to get into coding, you can use API plugins to add filters to your website. A variety of plugins are available to serve the task. For instance, WOOF is a great plugin for adding filters to website API. Another worthy mention is FacetWP which allows you to put on various filters with added visual images.