Here are some resources

https://www.swpc.noaa.gov/noaa-scales-explanation

https://en.wikipedia.org/wiki/Carrington_Event

https://science.howstuffworks.com/solar-flare-electronics.htm

Update — May 10, 2024 at 8:11 PM EDT

On Friday, April 12, 2024, at 6:54 pm EDT, extreme (G5) geomagnetic conditions reached Earth. This event followed G4 conditions first observed at 1:39 pm EDT and G3 conditions at 1:08 pm EDT.

Geomagnetic storming of varying intensity is likely to persist through the weekend, with Earth.com and the SWPC website serving as the best resource for warnings and alerts.