DDD, bulging discs and flat feet

I’ve had issues with my spine for a few years now. More pain in my legs (sciatica twice) and hips than my back.
I’ve heard a lot about how having flat feet is linked to back issues. I have somewhat flat feet which has caused me to develop calluses on the inside of my big toe.
I’d love some insight onto what that means exactly. What am I supposed to be researching and looking into? It’d be nice to hear from people who are similar to me too
Thanks in advance!