I would like to know how someone gets to be the proprietor of say a piece of land, what right did he have to get it?
This is a very difficult question which few have been able to solve in a satisfactory moral way. Some argue a form of Georgism is the way to go, while still others think use and improvement or homesteading is what matters. Maybe still others will think in terms of protection, like Johan Eliasch who bought up 400,000 acres of rainforest to protect it. Land is quite difficult to "own" because we can't take it with us and it varies widely in quality and availability. It's the home for other valuable resources as well. In many places it's abundant, but undesirable. In others, it's scarce and rich with value do to other externalities like climate, access, and proximity to other communities and resources.
Just because it was obtained immorally in the past by people who are now long dead does not mean we can't strive towards a moral ownership today. To the best of my knowledge, a market system is still the most effective way to determine value and transfer of ownership. Yes, it's massively distorted because of government and corporate banker interests which are directly part of government through their revolving door system and regulatory capture, but that doesn't mean the concept itself of voluntary, mutually beneficial trade via justly accumulated value is invalid. The "have nots" today still have opportunity to build a life for themselves and eventually justly obtain land, though it may take many decades for them while others may inherit it over night.
Nature is not fair. Life is not fair. It's noble of us to strive for equality of opportunity. Equality of outcome, IMO, is not only impossible but undesirable as well. Humans are unique and that leads to many differences.
On the conversation of property, land is surely the most complicated topic. That said, very few people today are actually using violence to obtain it.
Many financially successful people I know work much harder than others. It may not be physical labor, but it's no less taxing from a mental and psychological perspective, full of risk, hardship, failure, and determination. We all have our starting points thanks to our genes. We also have neuroplasticity to rise up and become just about anything we're determined enough to obtain.