Google can find quite endless lists of how much food it takes to survive a year for an adult... to that, you add layers of complexity that fit your personal situation. Nearly every site uses the phrase "for a year" and the language implies you can grow everything you eat for a family of 4 on 600 square feet. I don't believe it. 20 beans plants will not feed anybody I know for a year!
Here is a graph of traffic to our website. The yellow spot marks the beginning of Covid-19.
Obviously, besides toilet paper, interest in many homestead and home scale farming topics jumped.
In my calculations you are not supplementing what you grew with food from the store, its an attempt to calculate 'all in' requirements. Even then, are you just 'surviving' and playing board games, or, are you working like a Victorian farmer with tools powered by your aching muscles?
How many adults and children in your group?
Do you owe 'food' to the local landlord/government as was done in the past?
So, to attempt to determine the quantity of seeds to grow this food let's start simple: One adult eating 2,200 calories a day. That is slightly more that just 'surviving', but it is only half of what our Victorian-age peasant/laborer would have eaten. On a long & busy farming day, my exercise watches tells me I burned 4,500 calories. So keep that in mind, 'double' for hard working peasant life may be required.