When you "share" the text, the app passes it to the browser as a search keyword.
You can send the selected keyword as a search keyword to any other browser from the long press or share menu.

If the browser has a search interface, use the search engine set in the browser.
If the browser does not have a search interface, search on Google or you can select in the settings.

This app is a shared-only app and the settings screen will open when you launch this app from the app menu.
Also, by selecting your browser in the settings, you can skip the selection step and search with a single tap.