First time playing;would love advice on how to help the pups survive

As title says, first time playing!

Im really enjoying it so far!

I wasnt nearly as prepared as I thought id be for the death of my first pup :( she's one of two who got sick, and she didnt surivive. I dont want any of my other three to die 😭

I just hit the mission that says "survive through september"... any advice as to how to keep them alive? Is there are area that I should move to (can I move?)? Im currently in the bottom right of the map.