why does google come up in my search bar when opening Foxfire

Firefox is a web browser while the Google you are seeing in Firefox is a search engine. A search engine is for example duckduckgo.com, google.com, bing.com etc. To change to another of default search engine engines to use or install another one in Firefox then see https://support.mozilla.org/en-US/kb/change-your-default-search-settings-firefox