this is initial install of the firefox browser. How do I go to next step and run it?

I need help fully installing and running the browser.

See: *https://support.mozilla.org/en-US/kb/get-started-firefox-overview-main-features *https://support.mozilla.org/en-US/kb/tabs-organize-websites-single-window *https://support.mozilla.org/en-US/kb/keyboard-shortcuts-perform-firefox-tasks-quickly *https://support.mozilla.org/en-US/kb/mouse-shortcuts-perform-common-tasks