Overview
When you start the game, you will be on a train, and a cat will sit across from you and ask you some questions which will determine what you look like, your name,and town name. Then the train will stop and you will get off. As you leave the train station, a Tanuki (often mistaken for a raccoon in America) will talk to you and lead you to a small complex of 4 houses. You will get to choose one and then he will give a series of short jobs to do (It is basically a short tutorial) Once you are done, he will subtract a short total from your loan. Now, you can do basically whatever you want. You can get the money to pay off the loan by selling him stuff you don't need such as unwanted furniture or fish that you caught . Tom Nook's store is small at first, but will expand on buying and selling a certain amount of bells. When he expands, he will send you a letter in the game and posts on the board in front of town hall in .
Making bells
In the game, the currency is called bells. Each bell alone will not be able to buy you anything because of the bell's low value, you will need generally anywhere from 800-5,000 bells for a peice of furniture. However, you will get a large amount of bells for what you sell. You will also need to pay off your loan to Tom Nook with bells so once you have finished working for him, you should get to work and make some bells!
Fruit
Fruit is the most basic way to make money in Animal Crossing, however, it has its limits. The amount of money you make off fruit is determined by how many fruit trees you have and your town can only squeeze in so many fruit trees in the town and it takes 3 days for each fruit tree to replenish it's fruit. If you want to make some money using fruit, start off by taking anything in your equipment slot off, and putting all the stuff in your inventory into your house. Now step outside, and you will find a lot of trees that have fruit on them. The fruit on your trees are the town's native fruit. It will sell for only 100 bells but you have a large number of them in your town already. To begin, walk up to a tree and press A. Your character will shake the tree and three fruits will fall out. Walk up to the fruit and pick them up. Do this 4 more times, and then walk over to Nook's shop and go inside. Talk to Nook, tell him you want to sell, and then use the Y button to select each one and then select sell. You should get 1,500 bells for your entire inventory! Now you can repeat this until there is no fruit left in your town. If you have bought a shovel from Nook's, you can dig holes and bury fruit in them to plant trees! These will grow into full pledged fruit trees in less than a week. This is good money when you start the game, but as you advance further into the game and you have multi hundred thousand bell loans, this will start to become less and less useful. That's where non-native fruit come in. To start with, there is zero non native fruit in your town. But over time, villagers might sell you some for a few thousand bells, or you might take one from a friends town. You should plant it, and use all the fruit to plant more non-native fruit until you think you have enough. Now, when you sell your non-native fruit, you will get not 100, not 200, but 500 bells! That gets you 7,500 bells for each full load of fruit!