I find you have a good idea about the essay structure for this task. However, as Pahan suggests, I too feel your introduction needs improvement. It's better you introduce the argument first and then tell the reader about your position.
First, when you work at a job that is pleasant for you, you are eager to work better and you will not feel tired at all..
.... in this paragraph, you start with one reason;
First, when you work at a job that is pleasant for you, you are eager to work better and you will not feel tired at all.
... this is the reason ... ok?
Then you move on to another idea;
This eagerness to the work helps you to work more; also, your boss likes employees who are good at work and sometimes increases such employees' salary. In addition there is a chance to receive some awards when you work well.
....and support this with an example.
However, what you should have done is that you support the first reason with an example.