M why does my 2012 Honda Odyssey's battery keeps dying?

My 2012 Honda Odyssey has the wheelchair ramp with it
and the battery keeps dying way too fast. Both back
automatic doors won't close all of the way, but The lights
on the dashboard stay on telling me both doors are open.
The passenger side automotic door wouldn't open or close
at all either manually or automatically. So we had to turn off
the automatic door switch Because it would beep loudly
anytime we stepped on the gas. The battery kept dying
overnight and we would jump start it. I bought a new
battery in January and had no issues. Then about 2 weeks
ago, I was driving it and out of nowhere the battery light
came on, the "Check Charging System" message flashed on
the dashboard, and a weird smell was coming from the
vents from air conditioner running. I turned off the air
conditioner and as we were driving home it was jerking
forward constantly, literally running out of battery power as
we were driving it. By the time I pulled up to my house the
battery went completely dead and the entire van shut off. I
had to push it into my parking spot. I bought another
battery the next day and it started right up with no issues
except for the automatic doors not working and the lights
showing me their both open. Now again yesterday, I was
driving to pickup my son, and I was sitting waiting for him
to come out so I had it running for about 10 minutes. I
turned it off to save gas, and when I started it back up the
battery light was on again and the message "Check
charging system" was flashing on the dashboard. I didn't
want it to shut off again like it did before, so I drove straight
home. Once I got to my house and turned it off, it wouldn't
start back up again. I tried jumping it but the battery light
was still on and the "Check Charging System" message was
still flashing on the dashboard. Please help.