To fully appreciate this novel, you need to read the unabridged version, not Cliff Notes or some other shortcut used by students. You need to set aside a significant period of time for this (when I first read the novel 40 years ago, I used a week long break between school terms). The story is about a Russian nobel family and their friends and associates over an extended period of time. Young children grow up, get married, have children, and take over the family estates. It is set during (and after) the Napoleonic Wars, the setting being in Russia (to a very large extent in Moscow, but some on country estates).
Tolstoy was a member of the nobility and, by standards of the day, could have been considered a social reformer trying to improve the lot of the peasants. You will usually find a character in his novels that reflects his own attitudes (but not the principal character). He wrote and published novels in installments. To produce this properly in a film media would require making a lengthy TV series, somewhat like "Upstairs, Downstairs." I am surprised that has not been done.
The novel covers the rise and fall of the fortunes of the family and the people around them. The family's fortunes are shattered by a variety of circumstances including bad management of money and the French invasion. Partly the head of the family puts the welfare of others ahead of his own family. When the French are at the gates of Moscow, and they have wagons to save their belongings, they leave their own possessions behind in order to use the wagons to rescue wounded Russian soldiers.
Eventually, the next generation is left with the task of salvaging what remains and restoring the family fortunes.