In recent weeks, the star has at times shone more than 50 percent brighter than normal, drawing renewed attention from amateur sky watchers and professional astronomers alike. They hopefully await a historic celestial event. Someday, Betelgeuse will explosively end its life in a supernova—and from our planetary perch just 650 light-years away, we Earthlings will have front-row seats to this spectacular cosmic cataclysm.
Here’s an image that gives an idea of Betelguese’s size: https://www.jameswebbdiscovery.com/astronomy-news/exploring-betelgeuse-with-the-james-webb-space-telescope
It would! It is speculated that the supernova would be at its brightest for several weeks to a few months. It would appear as a star with the brightness of the Moon concentrated into a single point. We would see it during the day for several months to a year afterwards and we’d see it at night for a few years afterwards until it faded.