Living in hurricane country - we are always prepared to go at least a week with no power, and no ability to get food/water. Stored bottled water, food, batteries, propane for cooking, white gas for Coleman lanter/stove are always stocked up. So are essential first aid supplies, extra gasoline, and medicines, and yes, dog food.
An EMP is a much more severe scenario. Much longer lasting, more severe conditions. The loss of anything that worked on electricity in an instant.
Most of the population in the affected area will not survive past a year. As many as 80% will die from starvation, disease, and violence. The loss of 200 years of advancement and technology in an instant will mean certain death for many, like those in hospitals, or dependent on dialysis or daily medicine, while creating circumstances in which the region cannot support the present population.
Shelter, heat, food, water, sanitation, security, and essential medicines, will all present a huge challenge. You can stock up on ammo, but best to acquire some training in firearms usage right now. After an event like that is simply too late.