How much land do you think you would need to farm to feed 1 person for a year?

The rule of thumb used to be that a densely planted smallholding of about an acre (4840 square yards, 43560 square feet, about 4000 square metres) was enough to support a family of four provided that someone in the family did some casual labouring work to generate some cash to buy things that were not practical to grow and to buy pots, pans, spades, etc.

Some estimates are for much smaller area:
[quote]According to a UK study, to sustain one person on a vegetarian diet for an entire year, you’d probably need about 4000 square feet of growing space. This excludes access paths. That’s a big! Clearly, this amount of real estate will require a major committment in terms of your labor, too.[/quote]
https://www.almanac.com/video/how-many-garden-to-feed-family

That's only slightly more than one third of an acre for four people.

I'd say 5 acres would be ideal if you wanted livestock. You could get away with less if you lived off whatever you grew and kept poultry.

If it's planned and cared for correctly, and all the viable excess produce is canned, probably no more than a half acre.

Depends where you live...soils, moisture, growing season, etc.

I acre for vegetation

10 acres for livestock

Vertical hydroponics.. a courtyard

My mother's second husband had a quarter acre personal garden on his farm when she married him, then increased it to half an acre when we moved in, my mother and older brothers weren't much into fresh produce like him and I were, he was actually impressed that I knew how to cook vegetables other than boiled lifeless.