The King does work.
From the Official Royal Site here;
His Majesty has
worked closely with many organisations, publicly supporting a wide variety of causes relating to the environment, rural communities, the built environment, the arts, healthcare and education. \
Yes he gets a sovereign grant that he uses to pay for his official engagements and parties and fundraising events to support investments and charities and the like. It seems like a cool job, I would love it!
https://www.bbc.co.uk/news/explainers-57559653
Also, his duchy of Lancaster( which I think you mean
Lanolin) is his too and if you check it out he indeed gets money from rent and investments and puts a lot back into looking after the land and benefiting the local communities. He is a good king in my eyes. at least he didn't swan off abroad like my old landlord and spent most of his "rent money in Spain" whilst owning many housing properties.
This section explains the Duchy’s administrative role in the County Palatine, and profiles the other appointments for which the Duchy of Lancaster is responsible.
www.duchyoflancaster.co.uk