A couple of days ago, a solar eruption could have knocked up back to the Iron Age. Fortunately, the ejection came off the side, not facing the Earth. If it had, what would you do? Imagine a world with no electricity. We would have roughly 36 to 48 hours before the ejecta hit the planet.
Your number one priority would be water. The house that I live in is over 100 years old. There used to be a cistern in the basement that would have held 100s of litres of water. An average person requires two litres per day. I am glad I don't live in an apartment.
The next is to create food security. Once grocery store shelves are empty, there will be no refills. Transportation will be at a standstill, and the banking system will collapse. One hundred years ago, the majority of jobs were on the farms. Now it is less than three percent.
The biggest problem in the first years after the event would be that the early twentieth century's old farm equipment and horse population no longer exist. The more thoughtful people from the city would connect with farmers to become their labour and return to the technology of the nineteenth century.
Instead of being paid with money, the farmers will pay the labourers with room and board. My uncle worked for $0.25 per month plus room and board during the depression.