You need to learn how to do your bill paying. Get insurance policies in order. Know the passwords to take over whatever he has online.. check how his pension is set up to make sure it continues to come to you if he gets a monthly check. You will lose one of the SS checks if you both get them..you will get the highest. You probably should have taken over things when you saw him declining. There is so much to handle. The funeral home takes care of notifying SS for him..you will have to make an appointment toget yours in order. I suggest going in person.also, take someone with you as you visit different places. I had my brother..e took notes because your conentration wont be good and you won't remember most of what was told to you.

If you arent driving the car and wont be.sell it..you will need the money

Do and learn whatever you can now with your finances. Maybe have someone do your taxes if you dont feel hes mentally alert enough. You dont want the IRS on yourback.
Try to become involved now and take the upper hand if need be..