Sprint Goal vs Definition of Done (DoD)
1. In what ways does the Sprint Goal differ from the DoD?
2. Is the "Done" first defined during Sprint Planning stage? If not, in which Scrum event is "Done" defined?
3. When multiple Scrum teams share DoD, in which Sprint event is "Done" defined?
4. Is there a definition of Done against each item of the product backlog selected during Sprint planning?
Satam,
You would benefit (and find answers to your questions) by reading the Scrum Guide:
https://www.scrumguides.org/scrum-guide.html#events-daily
1. Sprint Goal and DoD are not at all the same thing so they differ drastically. One is a goal/plan, the other is an agreed upon criteria to determine if the goal is met.
2. DoD is something that should be updated regularly through an empirical process. If your team uses Sprint 0, it is usually crafted during that time and then updated as needed.
3. See #2
4. Maybe. I've seen it done both ways where there is a DoD that is applied to each story/backlog item and I've seen it where it simply applies to the increment. It boils down to whatever is best for the team.
Like Timothy suggested, read the Scrum Guide, then keep reading it regularly.