Space Weather Prediction Center
spaceweather.gov
spaceweather.gov
On days when I knew what was coming, it was (almost) fun watching ECC single-bit error counters ticking up across the O(100k) nodes...like watching popcorn pop in a hot pan.
And yes, it’s 2022 and I’m completely aware that I just recommended Wikipedia and two social media sites. I’ve taken the assumption that OP just wanted some general background, not a treatise on the dynamics of solar plasma and planetary magnetics.
Oh, and we are currently having a geomagnetic G2/G1 storm.
There's also a lot of material in ham radio circles on magazines, web sites and books about this stuff because it directly impacts radio propagation.