If you are familiar with other parts, you can read the introduction, roles, and ceremonies
The document describing the requirements and expected delivery is the most important document in Scrum. It is a bridge between product requirements and product implementation. A clearer description can reduce the possibility of the gap between the final product and the expectation.
The task is the specific thing to be executed. A User Story may be split into multiple Tasks, including tasks required by the front end and tasks required by the back end. Usually, a Task is the smallest indivisible unit.
The goal of Story Points is to measure the development capacity of the team within a certain period through quantitative indicators. Story Points can be defined in several different ways:
By everyone voting on the same Task, how many Story Points it should be, and obtaining quantitative standards determined by consensus, the purpose is to have a stable and measurable development volume. The purpose of judging by multiple members is to prevent senior members from evaluating the task with relatively low points, but in the end, the task may not be completed by senior members, which will increase uncertainty during delivery. Therefore it is very important for the relevant developers to decide on Story points.