Since 2014 Google has considered having an SSL Certificate on your website as part of their ranking signals, meaning having your site properly secured with a SSL Certificate can help you rank higher compared to competitors who don't use SSL.
While having https:// is considered a minor ranking signal, many website owners also see other indirect benefits such as improving the bounce rate (the percentage of people who find your site, but then immediately leave). Improving your bounce rate can help improve your overall search rankings - and it's always nice to have more people sticking around!