The biggest question you'll have to answer for yourself is - How much time do I want to invest? A walk-behind tractor is more than capable of doing what you're asking of it - but it's still a tool. You'll be providing the input of labor, the tool just enhances you.
You can do all that needs to be done with hand tools - spade, rake, shovel, scythe, mattock, axe, maul, wheel barrow, wagon. It'll take considerably more labor and more time, but it'll take much less money to buy the tools and no fossil fuel. It's also the most precise way to work. You can use the exact tool at the exact right time versus powered equipment.
You can do all that needs to be done with a 20-40 hp tractor. It'll take very little time and very little labor, but it'll take over $30,000 (probably much more, depending on which brand you buy) in equipment if you buy new. The biggest advantage this path offers is a loader. There's just no answer to what a loader can do. A wheel barrow or a trailer are poor substitutes. I wouldn't operate my farm without my skid steer loader (I do not like loader tractors. I own half of a 2040 with loader, but I seldom use it). Keep in mind, my farm is 360 acres with 200 acres tillable. I have 8300 laying hens. There's no question that I'm gonna have four wheel tractors and a skid steer loader.
And you can do it all with a walk-behind. It'll still take labor, but considerably less than with hand tools and a little more than with a four wheel tractor. It's the best balance between the two methods. You can buy all new attachments, spend around $10,000, and have about all you need to start - tractor, tiller, plow, mower, snowblower,
chipper, trailer. Like everything, you can spend WAAAYYYY more than $10,000 on the machine, depending on what attachments and how many attachments you choose.
Still, the question remains - How much time do I want to invest? You're going to be plowing at 10 inches a pass at 1 mph. You're going to be tilling at 27 inches per pass at 1-1.8 mph. You'll be mowing at 20" to 72" (depending on type of mower - sickle, flail, rough cut rotary, finish rotary, drum) at 1-3.3 mph. You can pull 1000 lbs on a trailer. You can blow your snow, chip your garden waste, split your wood, dig your potatoes, etc. Everything done while walking (the best exercise a human can ask for). But it's gonna take more time and more effort than with a four wheel tractor.
So - How much time do you want to invest????