How are jQuery powered elements in static html coded in WordPress?

I just took a WordPress course and started building very simple WordPress themes to practice, basically I download a free bootstrap template I can find online and convert it to WP, I use Advanced Custom Fields and Custom Post Type plugin most of the time. However some of these templates have a image slider, portfolio gallery, skills bar, twitter/testimonial carousel, tabs and accordion etc. which are powered by jQuery. When it comes to making the template dynamic how do WP developers deal with those? is it done using a WP plugin or they are manually coded?